Hotaruko
English name: Crimson Climax
Genres: Hentai
Type: OVA, Episodes: 3
Aired: Feb 21, 2003 to Sep 25, 2003
Studio: Arms
Source: Visual novel
Rating: Rx - Hentai
Synopsis:
Lured to a cursed island by a carnal cult, victims are brought to the throes of ecstasy, then brutally sacrificed in a bloody occult ritual. When sexy Ryo visits her late mother's island home, she's in for a terrifying surprise. Can she escape with her life and her virtue intact. 

(Source: ANN)