Mariko is happy that her daughter stayed at home after marriage, enjoying their two-generation living arrangement. She gets along well with her son-in-law, Takuto, but lately, his remote work has increased significantly. Furthermore, she frequently catches him indulging in masturbation... When she asks about it, it seems his cock is too huge, causing a sexless relationship with her daughter. Mariko, who has also been frustrated by a lack of intimacy with her own husband, uses the excuse of helping the young couple to service his huge cock until ejaculation. As she plays with his meat every day, the desires hidden deep within her begin to surge...
