Kenta can't concentrate on studying for his entrance exams because his parents are always fighting. During summer vacation, he is staying with his aunt Saki. He will be living under the same roof as Saki, whom he has had a crush on for a long time. He can't concentrate on his studies because he is distracted by Saki's soft-looking big breasts, which can be seen even through her clothes. In an attempt to solve Kenta's worries, Saki suggests a dirty way to refresh himself...