While her husband is away on business, Hijiri lives with her daughter and her husband who want to save money for their own home. Her days were happy, but as she got older, her sexual desire increased... One day, she finds out that her son-in-law, Kenichi, is watching her masturbate. Hijiri, who was excited by his extremely strong and splendid big dick, seduced him all the time. Kenichi, who has no sex with his wife, can't resist her charms and fucks him with his huge cock.