An Epic Crossover with Sekai and My Hero Academia, as the characters fight against each other in an all-out Battle Tournament!

In a world where humanity revolves around killing other human beings, it will take more than enough people to bring down a particular boy's insanity. As he, is the key to humanity's survival.

They lost it all, Their family -- The only thing they had, but now they have each other. Hartea and his brother Harashi venture the world for a place that they belong in...As they try to place the past behind them.