Diabolus: Kikoku
Japanese title: Diabolus～鬼哭～
Type: OVA
Episodes: 2
Source: Visual novel
Genres: Hentai
Studios: PoRO
Duration: 28 min per ep
Rating: Rx - Hentai

A spirit who takes the form of an attractive male is attacking many female students at a school. Two students discover that the only way to free him from his wandering around Earth is to have him fulfill his desire and so they decide to take a hands on approach and make him rest in peace at last.

(Source: ANN)