My friend's wife is a lewd private tutor

The father, who is not good at studying, is stolen by his son Tooru, who is not good at studying, decides to ask his friend's wife Mizuki to become a private tutor. However, Mizuki's huge breasts and sexy, powerful body makes her unable to study. Mizuki responds to Toru's erotic requests, with the exchange to concentrate on her studies... Mizuki was a lewd private tutor who uses her body to teach her everything about erotic things!