Aika who has become a multiparous woman and degree of fleshiness improves. Takuya Sano who secretly desires to his sister-in-law. "Do you drink? My breasts" One night, Takuya was unable to hold back his inferiority because of such Aika's selling word, which was made with the power of drunkenness... Since then, the two have been looking for each other's bodies in anticipation of when their families are gone...!?