Devil's Line

Devil's Line (デビルズライン) is a manga written and illustrated by Hanada Ryou.

Plot
Tsukasa, a college student, is rescued from an attack by a devil, one of many vampires that blend in among the human population. Anzai, her savior, is a half-devil who utilizes his devil-born gifts as a member of a shadowy police task force specializing in devil-related crime in Tokyo. As Anzai continues to keep guard over Tsukasa, the two quickly forge a tentative bond—one that Anzai fears will test his iron-clad rule of never drinking human blood...