Image imported from derpibooru 
Original Description:
 
Rarity wet her unitard. But she doesn’t mind, for it’s hardly the first time. She’s even having fun dancing and singing in her wet unitard. Of course a wave of water will rinse her off and hide all traces of her wetting. (She does get soaked by a wave of water in the actual scene, but that’s all she gets wet with canonically)
 
I did one of her peeing too (adding in a stream and puddle) but I think I’m rusty at the stream. If you still want to see it I could submit it and see how it’s received.