Hassaku Oji-san is an elderly man with black hair and black eyes. He appears across multiple episodes. His defining incident involves waking up trouserless and without underwear in tall grass near a railroad crossing after heavy drinking. Found in this predicament, he encounters Akemi and trades a hassaku orange with her for clothing; this exchange forms the core of the episode "Mr. Hassaku and I". The character reappears in other installments, including "SNS Siblings 2", maintaining his established role within the series' structure.