Higeki no Hiro

A young man dies in an attempt to save a girl from hoodlums one night, and awakens in a void he assumes to be limbo. A voice speaks out to him in this void, and ask him to destroy a great evil in his next life, offering him a boon to aid him. The boy who has always dreamed of going on such an adventure accepts and is sent on a journey to save the humans from a mad king of evil.