It's the beginning of the new semester at Yonsei University, and the students are getting ready for their assignments. One day, the professor asks the students to sit down and have a group chat. The professor is impressed with the students' ability to organize and organize their assignments, and he's impressed that the students will be able to get an "A+" on their assignments in just a few days. He tells the students that they should apologize to the professor for running away from the group chat, and that he'll make sure to do so again next week. The students are surprised to learn that the professor has been calling them lately, and they apologize to each other.