- "Kunisaki Chihiro, the 'National Treasure Eater'. Call me that from now on...!"
— Kunisaki Chihiro in "Oodenta Mitsuyo VS..."
Kunisaki Chihiro (國崎 千比路 Chihiro Kunisaki) is a second year at Oodachi High School and a former member of its wrestling club. After his loss against Ushio Hinomaru, he joins the sumo club.
He is tall, and muscular. He has short, black hair (greenish where the light hits) and sideburns, as well as sharp eyes, relatively long eyelashes and thick eyebrows He always wears a breathing strip on his nose. As an adult, during training, he had incipient facial hair.
Loud and brash, he's someone that relishes other people's attention. He tends to lighten up the mood, particularly when Kei is nervous or Yūma is being harsh on himself. Due to his attitude, he's also quite tactless and inapropriate. However, when the situation requires it, he focuses entirely on the match, doing his best to win, usually shouting 'STRONGEST!' to motivate himself. As such, he prefers individual competitions, even when he would still try his hardest in team competitions.
However, he's seen as holding an enormous grudge on his older brother, and the mere sight of him angers him due to bad history between them.
He's also caused some frustration in the others due to his less than stellar academic record. When he looked for support from others, he was shocked to find that both Yuuma (a former delinquent) and Hinomaru (a sumo head) were surprisingly good students, He decided to never fail a test again, but whether he made good on his promise was left unseen.
Kunisaki is an experienced fighter who seek to achieve the absolute top of the MMA world.
Before getting into the sumo, he already was renowned as the national champion of High School in Wrestling.
He demonstrated multiple times to have an overwhelming talent for martial arts, especially utilizing suplexes to throw opponents down, being described as a genius by both Ushio Hinomaru and Sada Mizuki, as he become able to copy opponent's special moves, like when he used Ushio's Demon Wheel to defeat Araki Gennosuke in their rematch. 
Despite the fact that he was practicing sumo for only a few months, during the Inter-High Tournament his skill level was already equated with that of a national treasure, considering that he had been able to defeat two of them – Hikage Tenma and Kanou Akihira – throughout the champioship.
After the end of the Inter-High Tournament, he moved to USA to pursue his dream about being a successful MMA fighter. Nowadays, with 20 years old, he already attained a champion title in a minor league (called MLFC).
When he was in fifth grade elementary, his parents divorced and he went with his mother.
He went to America to become champion and after coming back to support Hinomaru, it is revealed that he has a 10-month old daughter.
- Kunisaki Chihiro vs Ushio Hinomaru (1st battle: Wreslting Rules vs. Sumo Rules, conceded defeat)
- Kunisaki Chihiro vs Gojō Yūma (Sparring Match)
- Kunisaki Chihiro vs Ōkōchi Manabu (Kanto Newcomer Tournament)
- Kunisaki Chihiro vs Kuze Sōsuke (Kanto Newcomer Tournament)
- Kunisaki Chihiro vs Araki Gennosuke (InterHigh Tournament, Chiba Prefecture Preliminaries, win by Hinomaru's Demon Wheel)
- Kunisaki Chihiro vs Hikage Tenma (InterHigh Grand Sumo Tournament, Team Division - 1st Round)
- Kunisaki Chihiro vs Kanou Akihira (InterHigh Grand Sumo Tournament, Team Division - Semi-Finals)
- Kunisaki Chihiro vs Hyoudou Masato (InterHigh Grand Sumo Tournament, Team Division - Finals)
- He ranked fifth in the popularity poll
- He is the worst student in the club, having to take remedial classes to catch up, instead of training in Ishigaki High.
- His names his wrestling based special finishers by numbers. For example: #13 is arm-trap outside hip takedown.
- Has a tendency to loosen and crack his shoulders before matches to loosen up.
- ↑ Hinomaru Zumō Manga: Chapter 13, Page 15
- ↑ Hinomaru Zumō Manga: Chapter 101, Pages 18-19
- ↑ Hinomaru Zumō Manga: Chapter 104
- ↑ Hinomaru Zumō Manga: Chapter 122
- ↑ Hinomaru Zumō Manga: Chapter 205, Page 13
- ↑ Hinomaru Zumō Manga: Chapter 135, Page 7
- ↑ Hinomaru Zumō Manga: Chapter 136, Page 3
- ↑ Hinomaru Zumō Manga: Chapter 134, Page 12