My stepfather's wife is teasing me about my stepfather. Please forgive me now...

Aki is a wife, and she returns to her husband's parents' house with her husband for the first anniversary of her stepmother's death. His father-in-law, Koichi, had been targeting Aki for a long time, pretended he was mistaken for his dead wife, pushed him down and raped him. Aki is unable to even tell her husband, and is worried on her own. Knowing this, Koichi, who had been thinking that he could somehow manage to do something again while Aki was at his parents' house, puts a despicable strategy into action...