Exam Countermeasure of a High School Girl's Mom

Final exams are approaching, so the protagonist gives up his activities in order to study. As Kawaii, the school slut, is not ready for the exams, he asks his friend to help him pass with good grades. He agrees to help her, since he can use that time to study and because she will reward him with sex. After a few days of studying, the protagonist is left alone with Kawaii’s mother. As the two talked, the mother reveals to him that she knows all the kinky things he has done with her daughter. Just when he thought he was in trouble, the mature woman with huge breasts tells him that to thank him for all he has done for her daughter, she will let him have all the sex he wants with her.