School Days ONA
Genres: Drama, Romance
Type: ONA, Episodes: 1
Aired: Feb 25, 2005
Studio: Animation Planet
Source: Visual novel
Rating: PG-13 - Teens 13 or older
Synopsis:
The story is about a love triangle between the male protagonist Makoto, and the two heroines Kotonoha and Sekai. Makoto develops a love interest in Kotonoha, a girl in the same year but different class. Although they both take the same train to school, she is unaware of his existence. His classmate, Sekai, manages to put the two together despite holding strong feelings towards Makoto.

(Source: ANN)