Hostile? Never happened to me, not even in the early versions... I always healed him up and he was always the same - mumbling about how that wasn't necessary, how he didn't need any magic to heal him, "you think you're so fancy" and stuff. Then he recounts how he got beaten up and gives you the Sparkler card to win in the game. So he's grateful-ish.

Maybe it also matters which character speaks to him? I mostly play with Lohse as my main character, maybe his reaction is different for various characters...