School Days is a video game erotic published in 2005 by 0verflow for PC and PlayStation 2 and adapted into an anime of 12 episodes. The anime takes up only one of several implemented in the final game.
Makoto is a boy struggling with early heart problems. In particular, is in love with a girl he sees every morning on the train, Kotonoha Katsura, but which has not yet revealed her feelings. One day, talking to Sekai Saionji, his classmate, is helped by this to make the acquaintance of the girl and eventually the two begin dating assiduously.