Yoji has always been like a brother to his cousin, but all that changes when Yoji witnesses his cousin's wife masturbating one night. Unable to get the image of Kasumi's giant boobs out of his mind, Yoji makes it his mission to satisfy the unfulfilled woman. But Yoji's niece and Kasumi's sister want to get in on the action as well.

Yoji has always been like a brother to his cousin, but all that changes when Yoji witnesses his cousin's wife masturbating one night. Unable to get the image of Kasumi's giant boobs out of his mind, Yoji makes it his mission to satisfy the unfulfilled woman. But Yoji's niece and Kasumi's sister want to get in on the action as well.