The Dawn Of Ragnarok.

His classmates severely tormented him. Katsuragi Zora, a normal and average high school boy in japan, was bullied to an unusual extent that he bitterly hated humans. While wishing that he doesn't want to remain in isolation in this world, Zora musters the courage to commit suicide? After he dies, he gets instantly summoned into an unknown parallel space where time and space collide with each other.He naturally wonders where he is... "is this death? Will I finally be all alone after all those loathsome years? Abundant tears gently ran down his dear cheek and to properly answer his specific questions a kind unknown being invariably appeared he promptly told Zora that if he sincerely wishes to get revenge, he can generously help him. Zora, who was hopelessly broken to the essential core, naturally saw a sinister light of desperate hope "If you merely help me get rid of those arrogant bastards I'm even ready to inevitably become your wicked servant... the kind unknown being smiled grimly and said "The place you'll get your revenge doesn't exist anymore, instead I'll make an exception and send you to my world and I'll send those fools on whom you wish to take revenge! But remember with regret everything inevitably has a fearful price. The moment you step into that world you will take my place and be made to exact revenge on my behalf NOW, show those fools who dared to oppose me, those who betrayed me, if u satisfy my desperate hunger for vengeance you'll get rewards beyond your expectation."