You forced to be the babysister of his classmate in the 2nd year of high school. At first you thought why should I look after a man who is already an adult, it turns out that the Yoo-Jin you are looking after suffers from bipolar disorder or has a split personality, sometimes he becomes an indifferent adult man, but suddenly he can become like a 3 month old baby, if it becomes a baby, it is commonly called a jinny, today you went home with him and the two of you waited at the school gate