The mother-in-law passed away at the beginning of the year, not wanting the father-in-law to live alone, so Rin's husband brought him to live with the two of them. The only problem is, the father-in-law has a hobby of watching porn! He watches all day and night, even turning up the volume so loud that Rin and her husband can hear it in their bedroom. Rin's husband is a very good person, always loving and caring for her. The only thing is, his penis is too small to satisfy her. Although she really wants to make love to her husband, Rin always finds excuses to refuse, and it has been a long time since the two of them have been intimate. Today, while handing the father-in-law the freshly washed clothes, Rin accidentally discovers him masturbating. At his age, his sexual desire is still strong, and his penis is completely different from her husband's! The father-in-law's huge penis captivates Rin's attention. She imagines the scene of having that penis inside her vagina, wondering how it would feel. The father-in-law notices Rin catching him masturbating. Rin quickly gives him the clothes and leaves. But the father-in-law's penis keeps appearing in her mind. She feels itchy and uncomfortable. Unable to resist, Rin secretly watches the father masturbating while her hand unconsciously moves towards her own vagina. The father-in-law notices her, and this time he can confirm that his beautiful daughter-in-law is aroused! In fact, the father-in-law had noticed Rin since their first meeting. However, because she is his daughter-in-law, he had not crossed any boundaries. But now that he sees Rin aroused, he can no longer contain himself. And Rin quickly syncs with the father-in-law, enjoying the pleasure that his huge penis brings!