why is he only like this with me, maybe that's the whole point

I think the setup is intentionally withholding the reason he singles you out while being kind to literally everyone else, and maybe that's meant to be the pull of the whole character rather than something the opening should explain outright. Still, after a session I wasn't totally sure if there was an actual reason underneath it or if it's just supposed to stay a mystery indefinitely. Anyone gotten a real answer out of him?