Yuka has made a mistake that is unbecoming of a well-behaved teacher. She has become physically involved with her student Kobayashi. If she is found out, it will be the end of the story. With this bombshell in her heart, Yuka continues her relationship with Kobayashi carefully, but... Kobayashi, who is in his teenage years, is so obsessed with Yuka that he can think of nothing but sex. Not caring about Yuka's worries, he finally begins to desire sex at school. Yuka is completely confused by the situation, not knowing when or who might find out, but she also becomes submissive to pleasure...