|“||I am Theresa Gray, daughter of a Greater Demon and Elizabeth Gray, who was born Adele Starkweather, one of your kind. I was the wife of William Herondale, who was the head of the London Institute, and I was the mother of James and Lucie Herondale. Will and I raised our Shadowhunter children to protect mundanes, to live by the Laws of Clave and Covenant, and to keep to the Accords. Once, I lived among the Shadowhunters. Once I might almost have seemed like a person to you.||”|
Theresa "Tessa" Gray is an American warlock, a special kind of warlock—the only half-Shadowhunter, half-Eidolon demon. She moved to London in 1878 and her life has since been entangled in the lives of the Nephilim.
Theresa Gray was born to an unmarked Shadowhunter named Elizabeth Gray and the Greater Demon, Belial, disguised as the mundane Richard Gray—Elizabeth's husband and the man who would raise her as his own, and whom everyone believed was her father. Under normal circumstances, children of Shadowhunters and demons would be stillborn, but Elizabeth was able to give birth to Tessa not only because she bore no runes, but also because she wore the clockwork angel.
For much of her early life, she was unaware of what she truly was and her true parentage. Conceived in London, Tessa's family moved to New York while Elizabeth was pregnant with her. After the death of her parents in a carriage accident when she was only three years old, she and her brother, Nate, were raised by her maternal aunt, Harriet Moore. She spent the majority of her life being overprotected by her Aunt Harriet and looking after Nate, who grew up spoiled. Tessa, meanwhile, grew up finding comfort in books, dreaming of having the kind of adventures she read about. At sixteen, her Aunt Harriet died of what she thought was a fever. Upon her death, Nate arranged for Tessa to move to London with him.
Arrival in London
Tessa traveled from New York to London when Nate called for her, shortly after the death of their Aunt Harriet. Once there, a pair of mysterious and sinister women, whom she called the Dark Sisters, gave her a letter written in Nate's handwriting and told her that they've come to collect her on Nate's behalf.
The Dark Sisters soon revealed that they apparently had Nate as a prisoner, showing her their father's ring, one that Nate always wore, splattered with blood. They forced her to Change, or shape-shift, torturing her to learn quickly as well as threatening to harm Nate if she did not do as they asked. The Dark Sisters had made a deal with "the Magister" who had hoped to marry her and exploit her ability. In her isolation, she wrote letters to Nate about her loneliness and imprisonment.
One day, after Changing into Emma Bayliss, she was told about her marriage arrangement with the Magister, who had long been waiting for her. After a futile attempt to escape, she was finally rescued by the Shadowhunter Will Herondale. Tessa passed out in the midst of the fight against the Dark Sisters and was taken to the London Institute.
During her stay at the Institute, the head Charlotte Branwell promised to take care of her and help her search for Nate. There, Tessa befriended Jem Carstairs and the rest of the Institute's residents and staff, particularly Sophie Collins, the handmaid, while she had an uneasy relationship with Jessamine Lovelace, who wanted to move out of the Institute with Tessa.
When the investigation for her brother led them to Alexei de Quincey's house, she took the form of the vampire Camille Belcourt to infiltrate an exclusive party, with Will posing as her human subjugate and Magnus Bane, Camille's lover, as her guide. Once the human captive at the party was bitten, Will sent a signal to the Nephilim lying in wait to attack. Tessa then realized that the captive human was her brother, Nate.
During the battle, de Quincey went after Tessa, who was still in the form of Camille. Will, to save Tessa, fought him and ended up biting the vampire. After the battle, Nate was brought back to the Institute, where he was questioned and allowed to recover. Tessa got only a few moments with Nate since Jessamine, who wanted to marry a mundane so she can leave the Shadowhunter world, seemed insistent on caring for him instead, hoping Nate would fall in love with her.
Later, Tessa learned from Sophie that Will was being difficult about his treatment, which involved drinking buckets of holy water to bring up the vampire blood he had ingested, or else he would become a darkling. Tessa volunteered to take it to him in the attic, and Will finally obliged. During their rather intimate conversation, they shared their first kiss, before Will pushed her away and insisted that she leave him. After this evening, Will became even more standoffish and unfriendly towards her, much to Tessa's confusion.
To her surprise the following day, the Shadowhunters were discussing the further interrogation of Nate, possibly by the Silent Brothers. Annoyed, Tessa made it clear that their goals are not her responsibility, and that she did her part as they searched for Nate. Before leaving, she called them out for their pretentious attitude towards Downworlders and mundanes. After having some time to feel sorry about shouting at them, particularly since she was primarily only mad at Will, she left the Institute. She was promptly followed by Jem, who then began pointing out some places in London that might help her learn to love the city and even took her to his favorite—the Blackfriars Bridge. Here, Jem told her bits of his and Will's story and told her that he thinks she is no less human than him.
Unbeknownst to them, they were followed by a pair of automatons, one of them being the clockwork coachman of the Dark Sisters, under the Magister's orders. Jem briefly engaged them before running off with Tessa and got as far as the Institute before Jem collapsed, his illness striking at a bad time; fortunately, Charlotte immediately came to their rescue. During Jem's recovery, he told her about his illness, his body's dependence on yin fen, so she wouldn't blame herself.
When Nate woke up, he quickly devised a plan that he secretly told the Magister of but continued to bear the semblance of a frightened boy who wanted nothing more than to go home with Tessa and live a normal life. Selling her and the others lies and some half-truths about the true nature of his business in London, Nate falsely told them that de Quincey was the Magister and that the Dark Sisters would perform the binding ritual, a spell that would improve the automatons, that Magnus Bane had previously told them about on a full moon, the next of which was that very evening.
Nate's claim forced the Enclave to act immediately, leaving Tessa at the Institute with the non-Shadowhunters and the young ones, Jessamine, Will, and Jem. The mundane previously interrogated by Charlotte named Axel Mortmain then arrived and fed them false information about de Quincey and the Dark Sisters, telling Jem and Will where they were, prompting the pair to respond and leave. With the Institute now vulnerable, Mortmain revealed himself as the true Magister and attacked the Institute with his automaton army, intent on taking Tessa. Nate's connection to the Magister was also revealed.
When confronted by Mortmain, Tessa recalled Will's words to her earlier: explaining that the British warrior-queen Boadicea was braver than any man because she killed herself rather than let herself be taken by the Romans. With this inspiration, she realized that if she Changed into the form of a dead woman, particularly the Adams woman whose form she had already taken while under the tutelage of the Dark Sisters, she would bleed convincingly enough to make Mortmain believe she killed herself. By Changing very quickly, and for a very short time, she convinced him that she was dead and he left when confronted by Will.
Will, thinking she was dead as well, was momentarily affectionate towards her and showed his true feelings. Though he was happy to find out she was alive, he realized he'd have to put an even greater distance between them. Later, she came to Will with what she believed was happy news, that she was going to stay in the Institute, but he was unkind, treating her like a prostitute and revealing that she was unable to have children as a warlock. Tessa left, hurt and confused.
Over the next couple of weeks, Tessa grew closer to Jem, who volunteered to keep touring Tessa around London. She and Sophie also began being trained by the Lightwood brothers so they would be able to defend themselves. Tessa primarily worked with Gabriel Lightwood, which she suspected was his attempt to upset Will.
Meanwhile, the Institute was working on tracking down Mortmain. After a suggestion from Jem, they managed to turn up an old Reparations request filed by Mortmain against the York Institute for the murder of his parents. Tessa accompanied Will and Jem, up to the York Institute to meet Aloysius Starkweather and get the full report from his files.
A couple of days after their return, Sophie came to Tessa with an invitation to a masked ball at the Lightwood Chiswick house, addressed to Jessamine from Nate. Tessa sent Sophie to get Will for help and they hatched a plan. Tessa would Change into Jessamine and go to the party in her place with Will to get information from Nate. Will placed a sleeping rune on Jessamine so that she would not wake up until morning, and tied her to her bed as a precaution.
While at Benedict Lightwood's party, Tessa danced with Nate and learned that Jessamine had been betraying them for a long time, that she had supposedly even married Nate. Jessamine had passed on all the Institute's doings and planted a dangerous spell book in Tessa's room to frame her and get her arrested, to later be intercepted and captured by Mortmain. When they returned home, Sophie woke Charlotte who summoned a Silent Brother to interrogate and arrest Jessamine.
Later, Tessa once again Changed into Jessamine to meet Nate in a warehouse and hopefully learn Mortmain's location. However, it turned out to be a trap, as Nate had realized it was his sister he had spoken to at the ball. A fight broke out between Tessa and the Shadowhunters and Nate and his massive automaton. Will and Jem managed to blow the thing up, but it severely injured Will, who had covered Tessa from the blast, and killed Nate. The repeated shocks caused her to faint.
Shortly after she regained consciousness, Jem proposed to Tessa and gave her his mother's jade pendant as a token of their engagement. However, when Will arrived back from Magnus' house after the demon, Marbas, revealed that there was no curse on him, he talked to Tessa in private and declared his love for her. Painfully, she rejected him and told him that she did not love him and was engaged to Jem.
Imprisoned by Magister
Sometime after weeks of preparing for the wedding, Tessa finally realized that she was half-Shadowhunter, half-demon—an entirely new hybrid and immortal species that Mortmain wanted to progenerate with her.
She was kidnapped in an assault on the Institute at the delivery of Jessamine from the Silent City. Mrs. Black took her to where the Magister had taken up refuge in Cadair Idris near Will and Cecily's former home. Will soon came to rescue her, but his long trip was to no avail as he became trapped with her. That night, in the woes of her grief over learning of Jem's death and their belief that they would die the next day, she and Will made love.
The next morning, the rest of the Institute's Shadowhunters showed up, accompanied by Magnus Bane and three Silent Brothers: Enoch, Micah, and Zachariah—who was revealed to be Jem. In the ensuing battle against Mortmain and his automatons, Tessa Changed into Ithuriel to protect her loved ones and kill Mortmain. Changing into him momentarily enveloped Tessa in the angel's heavenly fire, which she was able to survive due to her Shadowhunter blood and the protection of Ithuriel.
Thanks to Charlotte's new command as Consul, she was able to get Jem to visit Tessa and properly cut their ties though a new Silent Brother typically isn't allowed to leave the Silent City for his first year. During their talk they dissolved their engagement, as Brothers could not marry, and made plans to meet once a year on Blackfriars Bridge so they would at least still see one another. Jem also gave his blessing for her and Will to be together. And, after having supported one another through their loss of Jem and slowly beginning a courtship, Will proposed to her on Christmas and she accepted.
For 25 years after the Clockwork War, Tessa, Will, and their friends and family lived in relative peace in London. Demons became so rare that they were able to live an almost mundane life; having balls and dances, boating parties, cricket matches, etc. They were even able to take holiday in the Herondale manor in Idris every summer and visit Will's parents for special occasions.
Of course, all that peace eventually came to an end. In 1903, London was plagued by a Mandikhor demon and its Khora demon offspring that were impervious to sunlight and brought down a poison the Shadowhunters had no cure for. Tessa focused her efforts on helping take care of the ill while they were being held in the Institute's infirmary whilst the Silent Brothers searched for an antidote. As such, it was Tessa who found Sophie's daughter, Barbara Lightwood, when she died from the poison.
Shortly after, the sick were moved to the Silent City and Tessa and her family grieved the loss of Barbara. Soon Tessa's own nephew Christopher had also fallen ill and the family was at a loss. Thankfully, the elixir Christopher had been developing was finished by his cousin, and Barbara's brother, Thomas later that day. Tessa's son James, with the help of Cordelia Carstairs, also managed to take down the Mandikhor and face down his grandfather Belial, who was behind the attacks. Tessa was not visibly upset by the news of her father's identity as she had been trying to find out for a few years and was satisfied to finally know; and grateful her son had survived the encounter.
At the Institute's meeting with Consul to discuss the recent attacks, Tessa was shocked at Tatiana Blackthorn's accusations that James had orchestrated the whole ordeal and burned down Blackthorn manor to destroy her evidence of it. She held a firm grip on Will while the subject was debated and questioned. Her astonishment deepened upon Cordelia's confession that James had been in her room the night of the fire. In private, Will expressed their disappointment to James in his treatment of women before he was cut off with the news that James and Cordelia were engaged. They were thrilled to have Cordelia as their future daughter-in-law but Tessa chastised Will for focusing his excitement on the simple fact of her being a Carstairs. Tessa then hastily threw together a traditional engagement party for them to properly celebrate.
Tessa and Sona worked hard to plan a grand wedding for James and Cordelia. At the reception, she helped distract the guests after Elias's outburst and later gave some company and comfort to Cordelia. She and Will gifted them a house on Curzon Street, a carriage, and Xanthos as wedding presents.
A couple weeks later, she and Will traveled to Paris to settle an issue there. Charles—who had been stepping in as the temporary head of the Paris Institute—had and forgotten to invite the Marseillaise vampire clan to a meeting of the vampire clans of France. The clan believed it to be intentional and took offense as Charles did not apologize, Will and Tessa had stepped in to resolve matters as they were respected in Downworld. They brought with them the Mortal Sword as a show of good faith and honesty.
Once things were cleared there, they raced home with the Sword for Thomas to be tried as he had been arrested under suspicion of murder. After Thomas was proved innocent, Leviathan attacked the Institute while trying to cross into the world and she fought alongside her family and friends. After the battle, when trying to figure out how this had happened, Maurice Bridgestock accused Tessa and her offspring as being the problem for having demon blood and being among Shadowhunters. Her son defended her and explained that another demon was behind the murders and using them to summon Leviathan. He planned to tell her and Will the full truth—that it was Belial—later.
That night, she and Will were visited in their bedroom by Jessamine, who informed them of Lucie's necromantic abilities. She was initially skeptical of Jessamine's claims but agreed with Will when he decided to speak to her.
Tessa stayed with Will until his death in 1937. Afterward, Tessa left London and stayed in Paris for ten years. She shared an apartment with Magnus for the first five, and he, along with his friends Catarina Loss and Ragnor Fell, helped her cope with her losses. During this time, she had a brief stay with Catarina back in London for World War II. Despite her children continuously asked her to leave for New York, she and Catarina shared a small apartment and worked as nurses with the nearby hospital, St. Bart's. She was almost thankful for the war as it gave her something useful to do that kept her distracted from her grief. Luckily she was there when Brother Zachariah was injured and brought in. After nearly dying, the two of them found their way back to one another as he had kept his distance feeling he could not comfort her grief. It was that night that Tessa learned there was a lost line of Herondales somewhere out there, and she asked to be a part of his quest in finding them, for Will.
While she hoped not to have to go through the pain of seeing her own children grow old and die, she remained in contact and still visited them and her grandchildren often. She also went back to using 'Gray' as her surname.
Two years after the Uprising, Tessa was staying with Magnus in New York when Jocelyn Fairchild came to ask him to protect her daughter, Clary. Tessa, in the place of an Iron Sister, then performed the Shadowhunter children's ritual on Clary with Brother Zachariah. Pleased to meet her, Jocelyn took up the surname "Fray", a portmanteau of Fairchild and Gray, in honor of Tessa's friendship with her ancestors.
Saddened by the Uprising, and the thought that the Herondales, the line of her and her husband, were gone, Tessa retreated to the Spiral Labyrinth and spent most of her time there, away from the rest of the world and its troubles. She instead focused on her research as a more scholarly warlock, aiding the Nephilim on occasion.
In September 2007, Tessa participated and fought in the Mortal War at Alicante. Some time after the battle, she found out that Stephen Herondale's son, Jace, was in fact alive. She hoped to speak with him, though Magnus told her to give him some time to accept his own lineage before she burdens him with the past. While speaking with Magnus, Clary noticed her and even vaguely remembered her, thinking she was familiar, but did not remember from when. At that time, Tessa was wearing white, mourning certain deaths, such as Ragnor's. Tessa returned to the Labyrinth afterwards.
Not long after her return to the Labyrinth, they caught word of a cult by the name of the Crimson Hand involved in several deaths and disappearances. They sent Tessa to infiltrate the cult by impersonating one of its members. However while at their headquarters she was exposed to a potion that made her lose control of her shape-shifting abilities. She was able to escape but barely, and had to be treated for injuries by Catarina.
They then heard rumors that the new leader of the cult that had whipped them into shape was their original founder: Magnus Bane. The Spiral Labyrinth wanted to go to the Shadowhunters and turn him in but Tessa begged them to give him a chance to stop the cult and prove his innocence. When they agreed, Tessa went to Paris to issue the summons on Magnus and explain all the information she did know that may help him.
Some days later, Magnus called on Tessa to give her the full story of his adventure in putting an end to the Crimson Hand. After he was done Tessa—who appeared as a Projection—said she would not give the Spiral Labyrinth all the details and would in fact tell them something entirely different but that would still clear Magnus of any guilt. Before she departed Magnus asked her for advice on dating Shadowhunters, to which she tried to help and wished him the best.
In January 2008, during their annual meet-up at the Blackfriars Bridge, Jem surprised her by arriving as a mortal, no longer a Silent Brother nor dependent on his yin fen as he has been cured by Jace Herondale and his heavenly fire. Though surprised, Tessa welcomed him back into her life wholeheartedly, and the pair rekindled their relationship, sharing a kiss at the bridge. They agreed to see the world together, and Jem told her the "story of Lightwoods and Herondales and Fairchilds".
In May, they attended the wedding of Jocelyn and Luke. There, Jocelyn formally introduced her to Clary, who slightly recognized her. During the conversation, Tessa told Clary that she felt a kinship towards their families, and gave her her copy of the Shadowhunter's Codex, as well as the Herondale family ring that was once her son's, James, to pass onto Jace. While Jace has finally accepted the Herondale name, she, and Magnus, still opted to give him a bit more time to adjust and be happy on his own.
Eventually, Jem and Tessa got married in a mundane ceremony—believing a real one would put their friends and family in danger. In 2010, Magnus decided to use oneiromancy to have a dream wedding for them. Their loved ones' souls were able to attend and be safe, but they would not remember it as the couple and Magnus would. Magnus officiated and they had it on Blackfriars Bridge in London. Towards the end of the dream, Will's spirit made an appearance to congratulate them.
Though they had found the the Lost Herondale—a line descended from Tobias Herondale—many years ago, Tessa and Jem were still looking to find out why she had to stay hidden. In 2012, they found a lead in the Buenos Aires Shadow Market that could tell them more about the threat. With the help of Alec Lightwood, they were able to gain access to the Shadow Market and speak to Mother Hawthorn. She told them the story of the First Heir and how she had fallen in love with Roland Loss. How the Unseelie King had sent the Riders of Mannan to kill her to keep the prophecy of "Faerie falling under shadow" when she reached for her full power secret. That they still hunt her line to this day to prevent it from coming true.
They soon began their search for her again, worried she did not know the true danger she was in and needed to be warned. Their search culminated in August 2012 when Rosemary reached out to them. Though they had been too late to save her, with her dying breath she asked them to save her son. After Changing into her, Tessa got a lead on where he may be and, following that lead, the couple scouted the Shadow Market. Her power to Change acted up during the trip. After she was fatally injured, Tessa found herself stuck in the Change, ultimately saving her from death, and Brother Enoch informed her that it was because she was pregnant. Tessa waited until after they'd saved Kit Herondale and safely deposited him at the Los Angeles Institute with Emma and the Blackthorns before telling Jem.
Tessa was momentarily affected by the illness affecting the warlocks caused by the blight. She and Jem search for a cure but her own condition delayed their search. Eventually, Tessa recovered, proving to be the only warlock immune to the illness, and she devoted her time to finding a cure at the Spiral Labyrinth. When the cure was found by Emma and Julian, Tessa asked Emma to look after Kit and keep him away from battle. The precaution failed when, during the battle against the Cohort, Kit engaged the Riders of Mannan and unleashed his magic, though they managed to cover up the act as Ragnor Fell's.
Tessa visited Kit in the Silent City, where they kept him after the battle during the moments when they gauged the threat to his identity, then asked him to move with her and Jem to Devon and be part of their family. Tessa was surprised but pleased to hear Kit accept, and they left soon afterward. They moved to Jem's house Cirenworth in Devon, England.
In March 2013, Tessa went into labor in the conservatory, with Jem playing on his cello to try and soothe her while she paced around the room. At that moment, the ghost of Livvy Blackthorn entered unbeknownst to anyone in the room, and started having thoughts about entering Tessa's unborn child to have a chance at a second life. Ty's voice, however, called her back to reality; in her shock and distress, she caused the walls of the conservatory to explode, alarming both Tessa and Jem, who thought it might be demons. Magnus Bane appeared and, noticing Livvy, assured them that all was well. After accepting some herbs from him, Tessa allowed Jem to walk her back towards the house, where she later gave birth to her daughter. They named her Wilhelmina, after their beloved Will, nicknamed Mina.
Tessa and Jem's family, which now included Kit and Mina, fell into a sort of routine. She and Jem continued to take care of and make Kit feel loved and comfortable, helping him come to terms with his losses.
Personality and traits
Tessa is an intelligent person. She is brave and strong-willed, and is incredibly caring. While she is generally warm, kind and understanding, Tessa can sometimes be very stubborn. She is also immensely curious and intensely determined when she decides to be.
Tessa has smooth, thick, wavy brown hair—which stopped growing half-way down her back when she stopped aging—steely gray-blue eyes, an oval face, and a slender body. She is around 5'9—considerably taller than most girls and boys her age (before she stopped aging) at that time. While she used to think herself average, several of her friends have noted that Tessa is pretty and beautiful; not conventionally beautiful, but kindly attractive. Being immortal, Tessa stopped aging at 19; though most believe she appears in her early twenties.
According to Aloysius Starkweather, she strongly resembles her maternal grandmother—his daughter-in-law.
Skills and abilities
- Immortality: Tessa is immortal, having maintained her youthful appearance since the 19th century.
- Magic: After gaining the ability to perform basic warlock magic, Tessa began practicing magic over the years and has even spent some time researching among warlocks at the Spiral Labyrinth.
- Changing: As a child of Belial, the greatest of Eidolon demons, she has inherited the ability to Change; the demonic power to shape-shift into another person. Unlike ordinary Eidolon demons like Mrs. Dark, Tessa can become whomever she transforms into as long as she has a physical object of theirs when she first turns into them. She achieves the Change by linking with a psychic impression or remnant of a person contained within an object. She can also Change by linking with a person's soul, as she did when she Changed into the Angel Ithuriel. In addition to their physical presence, Tessa is also able to touch the mind of a person and access their memories and thoughts when Changing, taking on their memories, mannerisms, and abilities.
- Clockwork angel: the clockwork pendant designed to protect her. It was given to Tessa's mother by Mortmain. It contained the angel Ithuriel's soul and when he was freed, Tessa stopped wearing the necklace.
- Jade pendant: the whitish-green pendant Jem gave Tessa when he proposed to her. It was first given to his mother by his father. It has Chinese characters carved into it which translates to "When two people are at one in their inmost hearts, they shatter even the strength of iron or bronze," from the I Ching, the Book of Changes.
- Pearl bracelet: the bracelet Tessa wore for her wedding with Will. The marriage runes were placed on the bracelet instead of her skin. On their thirtieth wedding anniversary, Will had it redesigned with pearls.
- Gold alethia crystal: an aletheia crystal gifted to Tessa from Will for their fiftieth wedding anniversary in which Magnus had helped him capture a happy memory. She has always kept it with her as she moved.
|“||I could not have loved Will so much if I had not loved you as well. And I could not love you as I do if I had not loved Will as I did.||”|
–Tessa about her love for Will and Jem, Clockwork Princess
Will was the first Shadowhunter that Tessa met. Will started out trying to keep his distance from Tessa, under the belief that he was cursed with endangering the lives of those who loved him; when this was disproved, however, Will immediately confessed his true feelings for her. It had been too late, however, as she had just accepted Jem's proposal.
Jem Carstairs is Tessa's current husband. Before he joined the Silent Brothers, they were engaged in 1878. When Jem was restored to his former, mortal self, he met with Tessa on the Blackfriars Bridge, as they had every year since he joined the Brotherhood. When she found out that Jem had no intention of returning to his life as a Shadowhunter, and when Jem was unable and scared to tell her how he was feeling at the time, she asked him to be with her, to travel the world together. They immediately resumed their relationship and were married over a year after.
Charlotte Fairchild was the head of the London Institute when Tessa arrived. She was kind to let Tessa into the Institute, and let her stay there, even though she was not a Shadowhunter. They formed a close friendship and Tessa did what she could to assist Charlotte in keeping her hold on the Institute.Over the years, the two became like family. As such, their children would refer to the other as "Aunt" despite no blood shared between them. Eventually, Charlotte's younger son became parabatai with Tessa's son James, and they couldn't have been happier.
Henry is someone who Tessa came to think of as family. Though the two rarely spent time together, she trusted him enough to let him borrow her mother's clockwork necklace and return it safely.
Sophie Collins was the maid at the London Institute when Tessa arrived there. She was very kind to Tessa and they were able to trust each other. Eventually, they became the best of friends, which lasted long through Sophie's ascension and elder years.
Along with other warlocks Catarina Loss and Ragnor Fell, Tessa has become very close with Magnus Bane. For five years after Will died, Tessa lived with Magnus and he helped her cope with the loss of Will. Many years later, Tessa called on Magnus to assist with the birth of her daughter Mina Carstairs.
Tessa used to have a good relationship with Nate until he grew bitter and dissatisfied with his life. He became seemingly indifferent towards her, even willing to sacrifice her free will in exchange for his success—a revelation that shocked and hurt her. Despite this, Tessa loved her adoptive brother dearly and mourned his death, and even Nate seemed to express some remorse before then.
Harriet is Tessa's aunt, though not by blood—a fact neither knew during their time together. Harriet raised her lovingly, as she did her own child, after Elizabeth's death.
Tessa's parents died when she was quite young. Nonetheless, the few years they raised her were said to be full of love. They had, at some point, learned of what had been done to her mother and what she was, but loved and cared for her still, wanting only to keep her safe.After becoming a mother herself, she sent Jem on a mission to find out who her true father was. Though Jem could not figure it out, it was soon revealed that her demonic father was the Prince of Hell Belial. Tessa showed no emotion when finding out, simply saying that at least they now knew.
Tessa eventually reconnected with some of her descendants after years of separating herself from them. She has since met Jace—the last of the Herondales directly descended from Will and their son, James—as well as the young Blackthorns of Los Angeles, descended from her daughter, Lucie.
Axel Mortmain (also known as the Magister), wanted to marry Tessa and had the Dark Sisters train her so she could be ready for him. Tessa then got rescued from the Dark House by Will Herondale and Mortmain was very mad at the Dark Sisters because he wanted (and needed in his opinion) Tessa for himself. He attacked the Shadowhunters and eventually in Clockwork Princess, captured Tessa for himself to marry and use as the final key in his plan. She later Changed into the angel Ithuriel and destroyed him for all he had done and planned to do.
- See more here
- Tessa hates chocolates.
- Because of her Shadowhunter blood, Tessa is seemingly immune to the harmful effects of runes on other beings. Charlotte mentioned that they had attempted to use healing runes on her and the ink merely sank into her skin.
- After Will became head of the Institute, Tessa took to redecorating and renovating much of the Institute.
- While doing so, she uncovered a cache of scandalous letters between Charlotte's parents; which she only showed to Will.
- When around strangers, Tessa glamoured herself to appear older and look around the same age as Will.
- For their thirtieth wedding anniversary, Will took the bracelet Tessa wore on their wedding, which bore the wedding runes she could not, and had it redesigned with pearls.
- Tessa always wore the pearl bracelet given to her by Will on their thirtieth-anniversary and the jade necklace given to her by Jem when he proposed to her.
- As of the 21st century, Tessa apparently has around fifty living descendants.
- Tessa chooses to go by her "warlock name", a one syllable surname, Gray, as she does not want to be identified as a Shadowhunter, despite technically being a Starkweather by birth, and a Herondale and Carstairs by marriage.
- Unlike the majority of warlocks, Tessa's last name, "Gray," is the name that was given to her at birth, rather than one she created for herself.
- Jocelyn Fray formed their mundane surname "Fray", a portmanteau of Fairchild and Gray, as an homage to Tessa and her close relationship with the Fairchilds.
- While grieving over Will, Tessa would ask Jessamine if the latter knew where Will was. She replied that she did not know what came after death but that Will hadn't lingered and had moved on.
- Tessa's favorite ice cream flavor is ginger.
- Tessa talks in her sleep.
- During her time living with Magnus after Will's death, the pair developed routines. Though she eventually moved out when she realized that Magnus' flamboyant lifestyle was not for her.
- Over the years, Tessa has a kept a number of diaries addressed to different friends from her past—including Sophie.
- Clockwork Angel: 10th Anniversary Edition
- Character heights — Cassandra Clare on Twitter
- Clockwork Princess
- Clockwork Angel
- Clockwork Prince
- Fairy Tale of London, a Chain of Gold extra
- Chain of Gold
- Chain of Iron
- A Deeper Love
- The Last Stand of the New York Institute
- "She reverts to it after Will dies," Cassandra Clare on Tumblr
- After the Bridge, from Cassandra Clare on Tumblr
- City of Glass
- City of Heavenly Fire
- The Red Scrolls of Magic
- In Dreams Begin, a The Lost Book of the White extra
- The Wicked Ones
- The Land I Lost
- Through Blood, Through Fire
- Lady Midnight
- Lord of Shadows
- Queen of Air and Darkness
- The Lost World
- Forever Fallen
- Ladies and their powers, Cassandra Clare on Tumblr
- The Midnight Heir
- Cast Long Shadows
- Dead thing, Cassandra Clare on Tumblr
- Shadowhunter Army June 2021 newsletter
- Shadowhunter Army December 2020 newsletter
- Answered question, Cassandra Clare on Twitter
- TLH questions, Cassandra Clare on Tumblr
- Answered question by Cassandra Clare on Tumblr
- Wedded Union rune, Cassandra Clare on Tumblr
- Blood relatives — Cassandra Clare on Tumblr
- Shadowhunter Army August 2019 Newsletter
- An Illustrated History of Notable Shadowhunters & Denizens of Downworld
- Secrets of Blackthorn Hall
- "Tessa could have written to so many people throughout the years ;)" — Cassandra Clare on Twitter
- Interview; one of the first blurbs; statement from the site artist
- Chain of Gold teaser, wedding invitation — Cassandra Clare on Instagram