Little Lord of Karate

Kohinata Minoru is a college student at a college that is popular for its sports rather than academic orientation. He starts out as a gymnast alongside his friend, Nana, but is bullied by his gymnast seniors. One evening, a karate student at the college, Mutou Ryuuji, witnesses Minoru being bullied and comes to his rescue and drags him into the world of karate. Minoru makes new friends and learns some of their dark pasts, including a shocking death that reveals motives for revenge. (from Baka-Updates)