Revenge of the Demonic Incarnate

Warning! MC is a bloodthirsty psychopath! Eighteen years ago, a massive demonic possession occurred in the entire world. The panic spread quickly, as the hundreds of possessed people became violent and often committed atrocities until the army finally stopped them. Humans managed to contain the demons, and soon the possessed people returned to their senses. Some of them felt immense guilt over the horrific things they had done. Damon was a simple high schooler who had everything he ever wanted. Caring grandparents and a loving girlfriend. However, he lost his loved ones and sanity on a tragic day. He will become a vigilante and face villains with malicious people with as much brutality as possible. His revenge would not be pretty.