Yofukashi no Uta

Kou Yamori stops attending school after losing interest in ordinary life, and insomnia soon sends him wandering the empty streets after midnight. There he meets Nazuna Nanakusa, an eccentric girl who feels as at home in the night as he does, only to discover that she is a vampire. Kou decides that abandoning his dull human life for vampirism sounds perfect, but being bitten is not enough. To turn, he must first fall in love with the vampire who drinks his blood. His aimless nights suddenly gain a strange new purpose: understand what love really feels like, fall for Nazuna, and earn the nocturnal life he thinks he wants.