The Revenge Pathway

They are criminals, murderers, monsters.
They took everything he had and now he wants them gone.

Keiji was met by devastation caused by an organized crime group that even big authorities can't stand up to and years later he wants them gone, and he's willing to wipe them out... peacefully? His plan is to scare them so bad that they'll break apart without taking a single life and becoming the monster himself, though that will be difficult speaking his closest ally is obsessed with explosions and all members of the group are much stronger than him and will kill him without hesitation.
He didn't think this through.
(Oh by the way, I will take a completely different turn to the narrative then how the start appears, just a heads up, but I swear I'll circle back around to it)