Komui Lee コムイ・リー

He is the Head of the Science Division at the Black Order headquarters and the older brother of Lenalee Lee. A young genius scientist, he holds the highest rank among the Order's support staff.

Within the Order, he is typically seen wearing a white coat and slippers. His signature beret seems to conceal some sort of mechanism; members of the Science Division claim that sounds occasionally leak from it. He tends to work the Science Division staff hard and push them around; their feelings toward him are described as "99% trust and 1% murderous intent."

He is somewhat addicted to caffeine; without coffee, he cannot work and tends to fly into a frenzy (he is a coffee connoisseur who favors Blue Mountain).

He is an extreme troublemaker and a mad scientist. He suffers from severe seasickness and often gets ill when traveling by ship.

He has a pathological obsession with his sister; the mere mention of "Lenalee getting married" is enough to rouse him from the deepest sleep and send him into full combat readiness. Unlike Lenalee, he is primarily a comic relief character, though he can turn cold and ruthless at times. He also acts as a bulwark, protecting the Exorcists from certain high-ranking Order officials who view them merely as tools.