Dokidoki Kojin Lesson Oshiego wa Tajuu Jinkaku?!

Saijo Natsumi is a highschool student who is my cousin lost her younger sister by a car accident years ago.
I (Name: Kazama Tomokazu) took a job as a private tutor of Natsumi by a chance. There is nothing much to teach, because she excels at everything. As a matter of fact, I am only a conversation partner. One day, Natsumi seduces me in careless disarray. I am shocked to the point of paralysis. She comes closer, down on her knees, yank my pants down and starts sucking my cock.