Hiroyuki can't contain his excitement when his mother's friend Kotone decides to become a private tutor. That's not to mention her well-balanced face, but her huge breasts further stimulate his extraordinary sexual desire... Then Kotone noticed his gaze and teased and toyed with him as if to vent his frustration. Since then, Kotone has come every now and then under the pretext of being a private tutor, and continues to stimulate his lust and enjoy the hidden pleasure that her husband cannot experience...