Mutou Black

Meet the top delinquent from Mars! His name is Ukita Kikuchiyo and he's now trying to take over new turf on Earth after switching schools but due to living in Mars’ low gravity, he quickly finds out he's quite weak. Luckily for him however, after getting beat by a gang, he meets up with Shirokuma Fuuta, a practitioner of Aikido who teaches him the ways provided it’s only for self defense.