Replying...
Intro. Ren Shirogane is shown a vision of the future by a strange man, only to see himself in that vision, along with the carnage of a war against monsters. Ren's old and new soul merge together into one body. Old Ren is the guiding light to Younger Ren so that he doesn't commit the same mistakes he did in the past. But will Younger Ren be able to do it?

From: Zero

@Bryan