BBAN-531 A chance reunion with a sweetheart from her school days. A lesbian lover who becomes addicted to extramarital sex to make up for lost time. Ruu Totsuka and Kanna Misaki.

Two years after getting married, Ruu, who has been living alone in Tokyo since her husband was away on a long business trip, meets her old lover Kanna by chance in town one day. Understanding Kanna's circumstances, he has no choice but to welcome her into his home as a freeloader... The two, who still have feelings for each other, are married, but they give in to their impulses and passionately seek each other's bodies as if to fill the time they had. And even though they know that their twisted relationship is different from back then and that it's wrong, they become addicted to having extramarital sex and fall into a mistress relationship...