Kobayashi and Kasuga used to go back and forth between each other’s houses, but as time went on, it disappeared.
One morning, Kobayashi arrives at school just in time to be late, and runs into Kasuga there.
Kobayashi was called out, but he felt embarrassed to go to school with him, so he turned back the way he came to escape.
After school, Kobayashi will clean the gymnasium as a punishment for being late. For some reason, Kasuga was forced to join him.
When the work was over, they talked about the old days, but Kobayashi remembered that he had sex with Kasuga and became uncomfortable.
He tries to get out, but the door won’t open.
The two are trapped in the physical education warehouse.
Kobayashi took off his jacket as it was hot inside the gymnasium.
Seeing this, Kasuga also took off his jacket.
Kobayashi can’t stop pounding because Kasuga’s chest is so different from before.
Despite her feelings, Kasuga reveals that he is holding back from peeing.
When she heard this, Kobayashi thought she had to do something and looked at the plastic bottle in her hand.
思春期のお勉強 第3話 キスをしてみたいお年頃