He has a slim body and a charming appearance. His skin tone is very fair.
Due to pneumothorax, he can't participate in gym class activities and spends time resting alone. He's seen as unpleasant by classmates due to his frequent coughing. His muttering of "ridiculous" when hearing reassurances about his condition suggests he's insecure about it.

At a school reunion, he meets Sun-ho, his past crush, but feels out of place and goes outside to smoke. Sun-ho joins him, sparking a conversation he can't resist.

(Source: Namu Wiki, translated)