Yui lives with her daughter and her husband. The family lives a peaceful life, but one day Yui's underwear is stolen! "Who is this aunt's underwear ..." Yui is creepy, but the criminal was a son-in-law! The son-in-law, who has been fascinated by Yui's big tits for a long time, explodes her desires and finally attacks Yui! Yui, who was frustrated, does not refuse and is tossed by her son-in-law like a toy.