Forgive me... My brother-in-law's carnal desire

Shigeru and Ritsuko live in the house where Shigeru and Ritsuko live, until Shigeru's younger brother Yosuke takes up a job. However, this increases the burden on Ritsuko, who is busy with both working and working, and the relationship between the couple becomes awkward. Meanwhile, Yosuke gradually becomes attracted to Ritsuko...