Injuu Kateikyoushi
English title: Lesson of Darkness
Japanese title: 淫獣家庭教師
Type: OVA
Source: Unknown
Episodes: 1
Status: Finished Airing
Aired: Nov 29, 1996
Duration: 45 min
Rating: Rx - Hentai
Studios: PP Project
Producers: Pink Pineapple
Licensors: Media Blasters
Genres: Hentai

Seventy years ago, several mysterious murders occurred in Tokyo, Japan. Young, beautiful women were found dead, their bodies dried up like ancient mummies. Now young women are dying the same way and Miho, a 19 year-old college student discovers that a weird stranger is stalking her. While her best friend Azusa, is busy seducing their professor, she discovers he is not human at all, but a horrible tentacle-endowed monster! Now that his dark secret is revealed, both girls are on the run for their life, but can she escape from the hideous monster disguised as a mild-mannered professor?