Animal 1

(from ebookjapan):

Ichiro Higashi is a first-year student at Kawagishi Junior High School in downtown Tokyo. He is a gutsy boy who lives with his family on a boat on the river.

On his first day at his new school, Ichiro is made captain of the wrestling team, and out of frustration, he decides to pursue a career in wrestling...!

Ichiro's battle to become Animal 1, the strongest of all animals, begins!