The protagonist of the hentai, Mikoshiba-kun, by a strange coincidence got into a sketch club (he accidentally dropped his sketchbook and his drawings appealed to the head of the club). He was the only guy who joined it. The head of the club, Shibasaki-san, is a very strange and at the same time incredibly energetic girl. She has a beautiful body - huge weighty boobs of size five, a thin horny waist and a firm ass. On the very first day, Shibasaki announced that she had decided what the club would do in the near future - this choice was the development of an eroge (erotic game). However, in order to gather the right information and to illustrate sex in a quality way, a guy with drawing skills was needed. Mikoshiba-kun, you could say, became her guinea pig, who had to sketch in detail every lewd action that happened to him. What can't be done to develop a quality product...