The lesson was finally over. Joohyun let out a very deep sigh. She's free, at least for that day. It was hard. The kids were awfully unfriendly and so rude. But the most important thing, during the last minute of the session, one or two kids praised her for being good at explaining things, which made Joohyun felt a bit relieved. 

She went to the teacher's room to return the classroom's key to the class 3.2's homeroom teacher, Mr. Kim. When Joohyun entered the room, it was only Mr. Kim and another teacher who she didn't know yet. 

"Good afternoon Sir. I am here to return the key."Joohyun said after bowing respectfully at Mr. Kim. 

Mr. Kim smiled. He was a young man. When he smiled, his lips formed a very unique rectangular smile. "So, how was it?" He asked, although he knew the answer would be like what he expected. 

"It was hard, Sir. But I will work even harder than this."Joohyun smiled reluctantly. "Anyway, thank you so much for providing me with everything that I need. In the future, please take a good care of me." Joohyun bowed once again. 

"Cut it out. Don't be so formal towards me when it's only us around." Mr. Kim said. 

"But. . ."

"Just call me Taehyung, like you used to be," Mr. Kim or Taehyung continued. 

Joohyun didn't response and the latter quickly changed the subject. "Anyway, it's only the first day. You still have a long way to go. Please take a good care of your health because it's going to be hard." Taehyung said, smiling. 

Joohyun nodded, "Then, excuse me."