Her husband died early due to an accident, and her lewd sister-in-law, Kawakita, was invited by her brother and her husband to live together. Because she hasn't had sex for a long time, here she often has lustful desires that make her often masturbate, especially this desire became even more terrible once when she happened to see her brother and wife having sex with each other. Since then, she has cherished her own wishes and plans to be able to satisfy her needs. That was the day she wore a very sexy outfit to practice yoga at home, seeing her younger brother who had just come home from work, she constantly practiced other provocative and sexual activities. Although he was extremely restrained by his sister-in-law's charming body, she was bolder, rushed in and crushed him and began to fulfill her long-held wish. After that time, the two gradually appeared in love, their level of clumsiness increased markedly without being shy anymore, only suffering the poor sister who was cuckolded by her lewd husband and sister.