The tale of the fallen revenant

(This will be a code vein x multiverse but it will start off at fate grand order)
So.. you want to hear about a tale of one of the long warriors who became alone after his loved ones sacrificed themselfs for him and now he sits in a once lively home all dead and gone. He would soon get offered a deal... a deal that would bring back his dead friends and lovers. Let's see how this plays out.