Mei-chan is a serious and kind girl. - Her recent trouble is the big boobs inherited from her mother. - Mei-chan, who has severe stiff shoulders because of her F-cup big breasts, is given a massage by her disgusting sister-in-law. - A brother who cant stand the breasts of her well-developed younger sister. - Her hand becomes more and more erotic, fir her big boobs. - Brother? Is this also a massage?