Lacus Welt

A vampire belonging to the City Defense Unit and a colleague of Mikaela Hyakuya and René Simm. The person responsible for killing Yoichi Saotome's older sister. Although not a noble, he boasts high combat capabilities.

He does not overthink things and acts in accordance with his own desires. He feels absolutely no hesitation about killing humans and sometimes does not stop feeding until his victim is dead. He prefers the blood of young boys, finding the blood of young girls to be too mild in taste.

He has a friendly personality; he calls Mika by a nickname and frequently picks fights with him.