Devils' Line is a manga by Ryou Hanada. It began its serialization April 17, 2014 in Morning Two manga anthology. An anime adaptation by Platinum Vision is expected to premiere April 7, 2018. Vertical Comics has licensed the manga for release in English.
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...
Official English site