Antonia is flirting with the idea of wetting her panties - posing for the camera and letting out tiny squirts, so the fabric gets wet, but not saturated (as she's on her way out). The idea of a damp crotch excites her, and she teases you with glimpses of her wet pussy as well. By the time she's finished, the stain has spread over her arse, but there's barely a puddle on the floor - nobody will be any the wiser about her damp crotch!