Seiji Komori

Seiji is Yui's priest father who runs his own church. Not much is said about him, but prior to the start of the series, he suddenly had to go overseas for work and left Yui in the care of the Sakamaki's. In the anime, Yui finds out that he is not her real father after discovering his diary. He is later revealed to be a vampire hunter whom Reiji once hired to assassinate his mother, Beatrix.