What is "dosei"

is a Japanese adult social simulation game developed by Tactics, a brand of Nexton. It was released on May 23, 1997 for Windows PCs, the same day as To Heart by Leaf. The gameplay in Dōsei follows a branching plot line which offers pre-determined scenarios with courses of interaction, and focuses on the appeal of the sole female main character Manami Minase. The player assumes the role of protagonist Masaki Yamada who is living with Manami shortly after they have graduated from high school. Masaki earns money at a job, and when he returns home will have sex with Manami often; this process of work in the day, and sex at night repeats many times throughout gameplay.

Dōsei was re-released on September 14, 2000, with the title Dōsei Memorial Selection. The game's original soundtrack was released bundled with Moon soundtrack in August 2000 at Comiket 58. Four of the staff that created the game— Itaru Hinoue, Shinji Orito, Miracle Mikipon, and Shinory—later became four of the founding members of the visual novel brand Key.