She smiles "Wrong~" is all she says before she roars, a mystical force comes over you before you shrink down to about 5 inches. She pads over to you before squatting over your head, stopping just before you are tucked between the folds of her pussy. She waits like this for a few seconds, letting you get many good whiffs of her scent. The crowd begins chanting the word "unbirth" in a low growl, gradually getting louder and louder before they are practically shaking the stadium with their roars for a finisher. The Sphinx growls in pleasure as she sits down over you, sliding you between her folds, your body, still unable to move, is helpless against her.
It only takes a few seconds for you to come up against some kind of wall, you can feel it pulse very slightly a few times before you feel it open up for you, sucking you inside and closing behind you. You can still hear the crowd's cheers through your fleshy prison, muffled as it is, they still sound just as pleased as they did when you got sucked into her pussy.
Pleased with her work, the Sphinx lays down, rubbing over her belly. You feel a sharp pain in your lower belly that makes you cry out, later you feel your form fading. Well, not exactly fading, sort of... transforming into something new. After a few hours of this feeling you find it hard to think coherently. As you slowly lose your mind you drift into one of the most peaceful sleeps you have ever experienced.
--Three weeks later--
Another gladiator is thrown into the coliseum, slowly picking themselves up and looking around they see a pair of Sphinxes. One of them a bit shorter than the other. Before the gladiator knows it they can't move a single muscle under their neck by their own will. The Sphinxes smile and begin their game again, and this will surely happen again and again until somebody can outwit them in a game too unfair.