Eerie, quiet, the tension so thick you feel you could suffocate. Twilight's library, despite being one of the most peaceful, brightly lit nooks you've ever stepped inside, now has your throat tight and knuckles awkwardly clenched at your sides. Twilight Sparkle, the pony you have lived with for the last few months as an understudy now stands before you. She slowly flips the pages on a book lewdly labelled 'Human Anatomy and Mating, a First-Hand Account' with a naughty smirk on her face. You agreed to help her conduct an 'experiment' without questioning what it was. Now you find yourself under the effects of an obedience spell, and at the mercy of both Twilight and a friend she has invited over: Princess Ember, both of them eyeing you hungrily as they read in great detail how the writer felt as she mated with a human.
Their eyes widen as they reach another page, and they turn to each other with their jaws ajar.
"See Ember? All the right spots~!" Twilight squeaks, biting her lip and gently sliding her hoof across what you can now see is a sketch of a human male phallus.
"It truly looks like it could 'slay' a dragon if it got inside me~. Did we truly need to put him under a spell though? ${name} has always been willing to help, and... always been such a good friend." Ember sighs, flicking her forked tongue along her blue scaled snout and giving you a half-lidded gaze.
"Maybe not, but the estrus is bad this year. I... I didn't want to risk him saying no. ${name}, please come here and... loosen your pants." Twilight says, moaning ever so slightly at the last part. The dragoness and the pony giggle and coo as you approach, your body helpless to do anything but obey. Your fingers undo your belt, and Twilight trots forward first.