Mei, Emi, and Minoru are childhood friends who attend different schools. On a night when Mei's parents are away on a trip, they have a long-awaited sleepover. In fact, both Mei and Emi secretly harbor feelings for Minoru. During a pleasant time, the three of them try drinking whiskey for the first time, brought by Mei, but they quickly get drunk. Mei, who is intoxicated, becomes fascinated by Minoru's virginity story and eventually falls asleep in bed. Minoru, left alone with Mei, is overpowered and drowns in his first pleasure. Returning to the room with his excitement still high, Minoru ends up having sex with Emi as well. And the three childhood friends who love each other cross the hot line that they can no longer be just friends that night──.
