For a decades ago,a infecteous demon has ran out of prison.

And has a power to infect all living things into a monster.

The war is declared by the demon king

shinokohara .

In this war all the human beings were died.

After it,the monsters are still alive in the present century.

There was a MDT (monster demolisher team) has 678 c rank heroes,56 b Rank heroes,35a rank heroes and 26 s ranked heroes.

A poor boy named Alex was roaming here and there in his village and thinking about something.

suddenly, An army of demons attacked the whole village.

The demons were keep killing the villagers.

there was blood everywhere.

Alex was very traumatized by seeing his parents killed by.

so he takes a knife and goes for the demons .