Mundanes, also called mundies by some, are regular humans.
Glamour and the Sight
Most mundanes are oblivious to the existence of Shadowhunters, Downworlders, demons, and the rest of the Shadow World. Occasionally, there are mundanes who are born with the Sight or gradually develop the Sight due to continued exposure to elements of the Shadow World.
When Nephilim, demons, or warlocks put up glamours, it is so that mundanes cannot see them; the mundanes see either something they would understand or nothing at all. These glamours can be put down willingly, though. Having the Sight allows some mundanes to see through glamour.
Relations with Downworlders
Mundanes are sometimes lured by faeries into their revels and their land, "adopting" them and turning them into beings as close as possible to faeries. Sometimes, strong mundane children are stolen by faeries and switched with their sickly own in order to strengthen their bloodline. These mundane children taken in by faeries are called changelings. The longer the mundanes, whether the stolen adults or children, stay in the faerie realms, the more faerie-like they become, with some physical fey attributes, attitudes, and the ability to perform some faerie magic trickling in.
Half-faeries can also be born out of relationships between faeries and humans, whether mundanes or Shadowhunters. Some half-faeries retain some faerie-like attributes, and they tend to be somewhat immune to weaknesses that harm, and limitations like lying that affect, full-blooded faeries.
Mundanes can sometimes have children with demons. Sometimes, demons may (or may not need to) disguise themselves as humans and seduce mundanes, resulting in a warlock child.
Relations with Nephilim
Though it is the duty of Shadowhunters to look after mundanes, who are mostly defenseless against the demons prowling their world, many Shadowhunters look down on mundanes.
Mundanes can be turned into Shadowhunters through Ascension, or by drinking from the Mortal Cup. The process is not foolproof; in fact, it is dangerous and can result in death for the weak-willed. A possible reason to undergo Ascension would be for marriage to a Shadowhunter; otherwise, relations with a mundane who will not become a Shadowhunter will require their Shadowhunter partner to abandon his/her society and life as a Shadowhunter.
When mundanes have children with Shadowhunters, the children will be Shadowhunters since angelic blood is dominant.
- "Mundane" means ordinary, common, or banal.
- Cassandra Clare used this term to refer to regular humans in the series because her gamer friends called people who don't play Dungeons & Dragons "mundane."