Well, some people don't feel physical pain. They usually die pretty young, though. If this guy has no preference but can recognize emotions usefulness as a tool in his life (as Wolfgang noted, maybe his perspective is more one of works/doesn't rather than feels good/feels bad), then you don't have to worry about him.
For me, I prefer that my friends
enjoy feeling good rather than having no opinion about it, but it's not my choice to make. Oh no wait... I guess being friends with them is my choice!
