I don't know if it's available in this site or even in the internet cuz the manga(?) was translated in my country, and I'm just trying my luck.
It's about this school where students usually get into fights. The mc was weak n always got beaten. One day a new student arrived n his name was nemesis. He beat all the other students n became the top fighter. Turns out nemesis was the mc n the new name was a combination of his name.
Ps: Sorry for vague description
Every updates got me thinking who's gege killing next. I'm desentesize by now