Koakuma Hatsuiku Chu-! | 小悪魔発育チュ～！

University student Nakashimizu Hiro, by requesting from parents returning to the parents family during summer vacation. Eventually the shape, the one of wanting childhood friend younger and cousin younger sister that have not met for several years to tell study. Especially Hiro that cannot manage free time, it decided to undertake it pleasantly.

However the childhood friend that have not met after a long time have grown up to a pretty girl. To here cute, Hiro that tells study while tensing. Moreover, being sure to tell study, a lewd act is urged by the childhood friend why!! Leadership is grasped to timid Hiro with surprising swiftness...

Furthermore, cousin younger sister and younger sister, even best friend's younger sister also enters the war... With timid Protagonist, the summer of very erotic with girls that were strong and younger started!!