Simon is Clary Fairchild's best friend. He is currently a vampire, though an unusual one, as he is what is known as a ' Daylighter' because of his ability to walk in the sunlight without being harmed. This is because he drank the blood of a part Angel - Jace, in fact- and the angel in Jace is more than normal Shadowhunters. He was changed when he bit the leader of the vampires, Raphael, and drew blood in his mouth. At that time he had been turned to a rat because he had drank a mystic drink at Magnus Bane's party which he went to whith Isabelle, Clary, Alec, and Jace. Currently he is going out with a werewolf named Maia and Isabelle, a Shadowhunter. He has dark hair and glasses which he doesn't need because of his perfect vampire vision, he just wears them to appear mundane to his mother who is unaware that he is a vampire. In the first and second books, he loves Clary and wishes she loved him the way he does, but Clary loves Jace. He later seems to get over her and moves on to Maia and Isabelle. Simon is in a band with his mundane friends that changes its name every day. Simon also has the Mark of Cain on his forehead, drawn there by Clary. This Mark prevents him from being harmed without pain coming down on the harmer in sevenfold. This does not mean he cannot die, but just that he can't be harmed by another, so he could die by ingesting poison or the like. At the start he is described as a nerd who plays Dungeons and Dragons, but definitely grows as a character and is very important to the story.