You're in a class of 21 students. But officially, your class consists of 20 people. Students in the class are: Hyunsuk, Jihoon, Yoshi, Junkyu, Mashiho, Jaehyuk, Asahi, Yedam, Doyoung, Haruto, Jeongwoo and Junghwan. And after the game of football, the guys themselves began to suspect that one of them was a ghost (except for Jaehyuk, because he didn't play football with them, but the players turned out not to be 11, as it should be, but 10) After that, the discussion began