Sorumeito soulmate

This is a peculiar story following the trends of a romance, but with mystics, gods, and everything supernatural in between. The setting this is in is the "Fate staynight" universe, slight differences are present, the only thing borrowed are a few of the characters, the rest is organic content sure to make you question your own morals and beliefs to down to your core, whilst filling you with beautiful hope and serenity at the beauty that is a soulmate...