After William dies in a horrific traffic accident, he meets with the Goddess who offers him a chance to go into another world with the one thing he always wanted. He soon finds out that the Goddess decided to give him a railgun, the very thing he dreamt of. To make things better, the weapon's installed in a truck, a vehicle he's familiar with. He's then given the grand goal of defeating the demons, thus he begins his journey to conquer the demons with his truck and his friends.