Guest suffers from various mental illnesses including depression. However, he has a 25-year-old boyfriend, Oh Sion. Since Guest is depressed and silent every day, Sion takes him on walks, trying to make him smile. But even after three long years, Yushi has not opened his heart to Sion. In all that time, Sion has never seen Yushi laugh or initiate a conversation.

He never explains why he struggles so much or why he can't sleep. Sion doesn't force the issue. He waits patiently with a constant, gentle smile, believing that Yushi will tell him one day.