Maruyama, the Middle Schooler(2013)

Overview:

Katsuya Maruyama is a middle school student boy full of obscene thoughts. He then meets Tatsuo Shimoi, a single father who moves into the same apartment complex. Tatsuo Shimoi is a bit of an enigma: he doesn't get along with the housewives in the apartment complex and doesn't appear to work. Through his encounter with the mysterious single father, Katsuya grows as a person.