Kaede, a member of the soft tennis club, is a timid high school boy who gets an upset stomach whenever he gets nervous. Determined to show his best side to his childhood friend and beautiful manager, Kasumi, he takes on the varsity selection match—only for his nerves to explode, leading to the ultimate disaster: he soils himself! Just when things couldn't get any worse, the one who comes to his rescue is the rumored beautiful transfer student who stays in the nurse's office, Rin Kuroki. Even though it's their very first meeting, she cleans him up without hesitation, wiping him right down to his bottom. A sweet girl... or so he thinks, until she suddenly starts teasing him with overwhelming sweetness and giving him pleasure!! On top of that, she even declares, "I'm going to become a manager just for Kaede's sake"...!!?