History's Strongest Disciple Kenichi

Story:

The life of a 15-year-old schoolboy, Kenichi Shirahama, changes when he meets a new student, Miu Furinji. Seeing her talent and martial arts skills, Kenichi joins Ryoji's Dojo, the Heroes' Shelter, a place where the strongest masters of various martial arts and Miu's house gather. After the young man defeated a student of the karate section, he was noticed by the best fighters of the school. Since then, all his free time Kanichi began to devote to exhausting training at the six masters of Ryozampaku, as well as the opposition of the gang "Ragnarok", which considered him either as a possible ally or a threat to their plans.