Jonathan Christopher Morgenstern better known as Sebastian was the son of Valentine Morgenstern and Jocelyn Fairchild/Fray and the older brother of Clary Fray. He posed as Sebastian Verlac during the events of City of Glass in which he is the hidden secondary antagonist. He was the main antagonist for the second half of The Mortal Instruments series. Jonathan now deciding to keep the name Sebastian then later used the Infernal Cup to create Endarkend Shadowhunters to fight normal ones and Downworlders. He also wished to rule Hell with Clary by his side.