Knight of the mist

Denki was on vacation when he got pushed off the water falls resulting in his death. Denki went to the after life. There someone was suspected of working with the Devils the wrongly suspected denki and kicked him out. Denki later had to stay in a town sized area, this area was surrounded by mist. Denki made friends with some people who told him it was dangerous to pass the mist because all the mist meant the giant waterfall was on the other side. Despite the warnings denki went into the mist only to find the demon who pushed him off the falls and he also ended up getting kidnapped by this demon.