The protagonist Toru So records his overflowing fantasy situations in his "sex diary".
He has kept it secret and carefully guarded it, but .....
But his classmate "Chikage Hou", a beautiful and talented girl, finds the diary and uses it as a masturbation reading!
After that day, he and Chikage, who is a pervert, start fantasizing together and fulfilling Toru's fantasies about sex that he described in the diary!
Chikage also brings along a big-breasted girl named "Nao Ryuubi" and a childhood friend named "Rito Tokito".
The girls are willing to perform all kinds of sex games for Toru, and slowly the guy gets his own personal sweet harem for lovemaking!
