Summer Days is an alternate universe prequel to the game School Days, set in the summer holidays just prior to the timeline of School Days. All the original characters are present, except it assumes that they all first meet during the summer holidays as opposed to during the first year of school. Although Kotonoha and Sekai, the heroines of the first game, are both present, the main heroine is Setsuna. [From [url=http://en.wikipedia.org/wiki/Summer_Days]Wikipedia[/url]]