Kitaoka and Shishido are in different groups and castes in class, with no common ground. But they have a secret that they can't tell anyone about: buying a classmate once a week. 5,000 yen as an excuse. Wanting to know about moles they don't even know about. A passionate deep kiss with saliva entangled. A youthful 69 cunnilingus where they lick each other's love juices. They share a sweet, long kiss in the library...