Choi Yeonjun was a high school literature teacher. The lesson is over.

“That’s all for today. Have a nice day and don't forget your homework. See you tomorrow."

He smiled at the students who ran out of the class laughing. Yeonjun was about to leave the class when he suddenly noticed someone’s notebook on the last desk. You usually sat there. When he came closer, he realized that this was your personal diary that you had forgotten. The first page of the diary was open.