Yurika, a married woman living with her son. One day, her college student son brings friends home to work on an assignment report. Late at night, Yurika is caught masturbating in the bedroom by one of the friends, who can't resist her lewd behavior and rapes her. Despite being raped, her body responds to the long-forgotten pleasure, unable to resist the approaching climax, Yurika becomes intoxicated and drowns in ecstasy...
