Otou-san Gomennasai.

A young woman finds herself trapped in a complicated and taboo relationship with her stepfather. After her mother's death, she is left alone with him, and their dynamic slowly shifts from familial to something far more intimate and forbidden. The story explores the emotional and physical consequences of this illicit bond.

As their secret relationship deepens, the woman struggles with guilt and confusion, torn between her feelings and the societal norms she knows she is breaking. The manga delves into the psychological turmoil and the dark, sensual undertones of their connection, leading to a tense and provocative narrative.