A clumsy and shy kid.
He was bullied a lot at school and lived in a strict household were perfection was the key word. He was the typical fat and shy kid with big glasses and weird personnality, bad in physical education and always alone. During his childood he focused on his studies to met his parents' expectations. Ban's only way of escaping was anime and manga, where everything was different and no one could judge or hurt him. Time after time, his perfects grades started to degrade as much as his mental health,under the pressure he became very withdrawn and at 18 he ran away from home.
It's when he tried to isolate himself in the woods that he met Koyuki, someone who seems as lonely as him. Afraid of this strange grumpy old man who accepted him in his house for an unknown reason, he did his best to gain his place and prove himself to someone once again. Even if he get scolded a lot, slowly their drasticaly differents personnalities will start to draw them closer together.