I'm sorry but, 280 words? I don't expect novels (I'm sure no one here does) but that's just way too short. There was almost no detail. "She felt sudden relief as it all came out of her system." All of what? We didn't even know if she had to pee, poo, powder her nose up until she sat on the toilet, even then it was fuzzy. Make sure your audience knows what's happening in a scene, that's very important for erotic fiction.