Based on the erotic game by Space Project.

The hero is an "ordinary student," Tsukui Shinichi, now in his senior year. A long-lost childhood friend, Ayase Aoi, moves in next-door and transfers into his school. Shinichi can't quite remember Aoi, which upsets her quite a bit. Her good looks attract the attention of Shinichi's comic sidekick, Yamashita Satoshi, and the school playboy, Kanzaki Kotoro. While Shinichi and Aoi spar over a potential relationship, Shinichi crosses paths with and then beds other students, including a clumsy genki girl, Fujiro Mami; an aggressive vamp, Ebina Mika; and the president of the Flower Arrangement Club, Hayama Reiko, before finally ending up in the arms of his destined True Love.

(Source: Orphan)