The guy that Gozu replaced when he "reincarnated" into the game's world. If you remember at the beginning he spawned as an assassin that was meant to kill Eve, hired by Eve's parents.
So, he was looking for the real owner of the body Gozu is in right now? But what about the flashback about letters? I don't get that either
I think the letter is Eve's love letter for Gozu when they were at Odigos's academy in the previous chapter. I forget which chapter but maybe roughly ch 60+
Wait wait, I know that their bodies rn are not the ones they're supposed to have, but who is the "he" that the guy who kidnapped Gozu is talking about?