Yoasobi Gurashi!

The story begins when Kazuto's childhood friend and model Yayoi asks to stay at his apartment without any explanation. Kazuto often sees Yayoi go out with a guy after leaving his apartment, and idly wonders why she won't stay at his place. One night, Yayoi asks Kazuto to not come home until morning after the graveyard shift at his part time job ends, since Yayoi is inviting a friend over. Kazuto guesses that she is bringing home a man to have sex with. When his suspicions prove true, a new relationship between them begins.