Fate/Alternative(Harem x Male Reader)

Y/N Mayfield a young man from the U.S. living in Fuyuki Japan. However what most people didn't know was that this young man was a mage and a pretty solid one at that. So he would be able to summon a high quality servant to fight in a Grail War right? Well this Grail was is a little different being that some people who aren't even mages being able to summon servants. As well as their being a left over servant from the previous grail war that took place in Fourth Holy Grail War. This War just got pretty interesting. The reasoning for being in Fuyuki you ask? Well he was tasked by a certain troll who not only sent him but also sent his two disciples to Fuyuki with the task of tracking this young man down for plot reasons.