Inyouchuu The Animation
Genres: Supernatural, Hentai
Type: OVA, Episodes: 2
Aired: Oct 31, 2006 to Dec 26, 2008
Studio: Suzuki Mirano
Source: Visual novel
Rating: Rx - Hentai
Synopsis:
Three students are in a school late at night fighting supernatural enemies.  As they are about to leave, they get attacked and trapped.  Based off the Inyouchuu game.