They could be disgusting or hot.
IMO it's the former if they play with the poop or have someone eat it. It's the latter if they just show the girl relieving herself.
Do you know that there are old gravure-like movies with scenes where the girl is taking a poop? I was surprised and excited the first time seeing it. One was this scene of a photoshoot session with a pretty girl taking a stroll on the beach. Sometime later she removed her bikini, squatted down, and relieved herself. It was really hot, maybe because you don't associate a pretty girl taking a poop but it could also because it was done so casually.