Nanase Ren
English title: Night Shift Nurses: Ren Nanase
Japanese title: 七瀬恋 (アニメ)
Alternative titles: Anime Nanase Ren
Type: OVA
Source: Visual novel
Episodes: 1
Status: Finished Airing
Aired: Dec 4, 2005
Duration: 33 min
Rating: Rx - Hentai
Studios: Flavors Soft
Producers: Soft on Demand
Licensors: Kitty Media
Genres: Hentai

This will appear to be a very disturbing animation to most. Designs by Murakami Teruaki, published by Soft by Demand (Anime), and based on the eroge by M no Violet.

(Source: Bakunyuu)

Note:

There are 2(!) Nanase Ren OVA. Produced by totally different studios, but both feature the same(!) character. The other one is the "Kranke Nanase Ren" (夜勤病棟　Kranke　七瀬恋) bit, which is a special for Yakin Byouto

(Source: AniDB)