After losing her husband, Asaka Tomita lives with her daughter and son-in-law. Lately, her daughter has been busy with work, often returning home late, causing her relationship with her son-in-law to grow cold. One night, the son-in-law is drinking alone while Asaka takes a shower. Running out of soap, she heads out to look for her daughter but unexpectedly encounters her son-in-law, who sees her completely naked. Flustered, he quickly retreats and begins masturbating from excitement. Asaka discovers him in the act, instantly creating intense tension between them. Amid the awkwardness, Asaka unconsciously reaches toward her son-in-law's crotch. They both know they must keep this a secret from her daughter.