While I agree this probably wouldn't be nearly as funny if it were a guy stalking a girl, the whole issue in general is kind of a mitigated by the simple fact that she doesn't actually seem to push the issue. She's not seriously hitting on him or anything, she's just following around from a distance. Not to mention, as stated, she does provide a very valuable service. She doesn't sit there and stare all the time.
Where if a guy doing the same thing, essentially providing a walking apothecary service but clearly had an interest in a female party member, but still at the very least didn't press it aside from staying nearby and admiring, I'd probably let it slide, although it would still feel skeevy.