His is invited to train there by Miu Furinji. After he learns a basic move from Miu he was able to beat a big guy from his Karate Club this is when he becomes a target of a fight club called Ragnarok. Ragnarok is made up of the best fighters that are ruled by the 7 deadly fists.
This anime was able to show that through hard work that anyone can become great. Kenichi beat Ragnarok and one by one he touches their hearts and you find out what went wrong with each of them why they had turned to a street gang and most of them become friends.
Kenichi and his Masters
(The History's Strongest Disciple)
(The Ultimate Martial Artist)
(The Philosophical Jujitsu Master)
(The Shinigami (Death God) of Muay Thai Underworld)
(The Invincible Superman and Miu's grand father)
(The Master of All Chinese Kenpo)
(The Prodigy of Swords and Master of all Weaponry)
(She is also becoming one of my favorite people in this story)
(The Hundredth Degree Street Brawler)