Tōyama, an unassuming high school boy who is introverted, is walking the streets at night in search of contraceptives while having sex with his girlfriend, Takai Yumi. He finally finds a condom vending machine. Just when he thinks he finally found a condom, his classmate Marika Uehara, a beautiful girl in the upper caste of his class, sees him. After that, he was a little annoyed that Uehara tried to involved with him in any way. Uehara, who he hadn’t any contact with before even though they were in the same class, was starting to take an interest in Tōyama.