Despite their similar looks, Alec is very much the opposite of his sister in the sense that he is
self-conscious and serious. In the special, "Kissed", Magnus describes Alec as straightforward,
and Alec says that he is blunt, as it is the only way he knew to be. Clary perceives that Alec
appears "uncomfortable in his own skin." This is possibly due to his fear of admitting to others
that he is a homosexual. He convinces himself to believe he is in love with Jace as a way to
escape his fear of being hurt by falling for Magnus. Alec is very protective of his family and
assumes the most responsibility as the oldest of his siblings. He and Jace are parabatai,
meaning that they are warriors who fight together and are closer than brothers.
He seems to pride himself in being allowed into the Court in City of Glass, him being the only
one of the Lightwood children to go.
Alec is often soft spoken and serious in most situations. He tries his best to act wisely, and is
shown not be as brave as Jace is; but cautious. Up until later in the story, he had never killed a
demon. However this is more because he puts Jace and his sister's safety before killing
demons, frequently putting himself in danger to protect them. He shows himself to be
extremely caring of the ones he loves, and is willing to do anything to save them, also he is
said to be "easily guilted". Between the whole group, Alec is the most clever. Alec, as seen in
City of Fallen Angels, can also become extremely jealous, getting angry at Magnus when he
discovers Magnus' long dating history and relationship with Camille, a vampire woman. He also
becomes jealous of Will, who he suspects as another one of Magnus' several lovers and, he
learned from Camille, is said to look extremely like him.