The Dark Fate Of Fantasy Season 1 (Natuverse/ TG/ FF x Male Oc)

At the event of the great fire in Fuyuki City, a young boy named Ren who lost an arm from the event, he had lost his memories. he doesn't know his family nor what happened before. He was saved by a man named Kiritsugu Emiya. who raise him after the years of the event but Kiritsugu Emiya was missing after a few years. Ren was left by an woman named Taiga and a girl named Tifa Lockhart who was also adopted by Kiritsugu Emiya. After a few years later Ren will be forced to be part of the forth holy grail war but instead of wanting the grail he want to destroy it and saved servants and master from the war.