A married woman, Yuu, grows frustrated with her husband's inability to satisfy her desires as he secretly masturbates. Left with no choice, she starts pleasuring herself, only to be caught by her neighbor, Mizusawa, through a window she forgot to close. Mizusawa apologizes sincerely, claiming no ill intent. Yuu feels his honesty and confides in him about her frustrations with her husband. As they discuss sexual topics, both feel changes in their groins. The two, who were never supposed to get involved, start an intense affair after this incident of being caught masturbating…
