Saitama's teacher

An unnamed man who was the homeroom teacher of Saitama's class when he was 12 years old.

Appearance
He has black pointy hair with bored and sleepy eyes and a big nose alongside with big lips and a cleft chin.

Personality
Like most teachers, he is serious and strict about his job. When Saitama forgot to do his homework, the teacher berated him. He is also the type who can't take a joke.

Background
One day, when Saitama entered his class forgetting to do his homework, the teacher berated him and told him to come to the staff room after school. However; due to Saitama being bullied and mugged by two upperclassmen while on his way to the room as well as later chasing Piggy Bancon in an attempt to take back his money, the teacher waited longer than he expected, thus he was angry at the time Saitama finally arrived. Despite Saitama explaining to the teacher why it took him so long to come, he still showed little to no sympathy to Saitama.

Quotes

 * (To Saitama) "While you are doing yesterday's homework, everyone else has moved on. One small slip-up today has ramifications ten years later! Don't you get that?"