After getting drunk in a middle-school class reunion, Ookawa Hiromi wakes up at home finding his former classmate Segawa Maki tucked in his bed. The two found out they actually slept together, though not able to recall any moments of the experience. Acting normally as if nothing happened, the two happened to meet together after a while and again got drunk and slept together. Hiromi had to move out from his apartment as it was going to be demolished while Maki is looking for a housemate after the previous one decided to move out. Will this be the trigger for them to start living together with a...