Alec Lightwood is a fictional character from the book series The Mortal Instruments by Cassandra Clare. He is a Shadowhunter, a human with angelic blood tasked with protecting the world from demons. Alec is known for his strong sense of duty, loyalty to his family, and exceptional skills in combat and archery. In the series, Alec is the eldest son of the Lightwood family and has a close relationship with his younger siblings, Isabelle and Max. He is also known for his romantic relationship with Magnus Bane, a warlock, which explores themes of love and acceptance in a fantasy setting.