Daimon-sensei (literally 'Teacher Daimon') is one of the few teachers who appear in the series. He is also the only male teacher who makes more than one appearance. He is the advisor of the Judo Club, training them to a high enough level that they were able to take part in interhigh competitions only a few months after the club was founded.
Daimon-sensei is a tall and physically imposing teacher. He is even taller than Takatoshi, who is noted to be quite tall already. He is physically in great shape and fully qualified to teach the Judo Club members.
He has a thick brown beard (but no moustache) and sideburns that connect to his hair at the back of his head. The top of his head is bald (something that he worries about).
Daimon-sensei gives off an aura of being gruff and strict, enough to ensure Naruko Yokoshima behaved herself on a school trip. He also has a softer side that shows when he is with his fiancee Michishita-sensei. He also worries about his receding hairline, to the point he nervously asks Michishita-sensei if his (balding) head isn't too shiny.
He becomes embarrassed when this softer side of him is discovered, and tries to hide it behind bluster. He is also a bit forgetful, as he once forgot to warn Mutsumi Mitsuba that someone was coming to interview her and take pictures of the Judo Club.
Daimon-sensei's fiancee. The two of them seem very much in love, as the otherwise gruff Daimon-sensei becomes bashful around her. During the 2nd Year field trip to Okinawa, he took the time to collect some star sand for her simply because she offhandedly mentioned she wanted to find some.
Locations associated with Daimon-sensei
- Ousai Private Academy
- Judo Club Room
- Daimon-sensei is actually the second male teacher to appear in the series. In Episode 10 of the 1st anime, a Mathematics teacher made a brief appearance instructing Takatoshi to answer a question on the board.
- Daimon-sensei's seiyuu has also voiced various other characters throughout the series, including the foreigner who asked Suzu Hagimura and Takatoshi for directions in Episode 3 of the first anime, the Beach Playboy and Ousai Headmaster Rikizou Kondou as well.