Your first reaction is to try to push him off, but you find yourself giving in to his advances.
You feel his hand slide up your thigh and rub your pussy through your panties and you feel yourself going moist. You see his pants starting to tent, and he gets up to take them off, along with his shirt and underwear. You see him there standing naked, hard from you. He moves back towards you and raises you to your knees with his cock in your face as he has you blow him. He precums in your mouth, and he gets back on top of you on the floor.
He pulls off the young girls bra you put on earlier and he toys with your nipples for a short moment. You feel a warmth between your legs as your pussy gets more wet and you get more horny. He then moves down and tugs off your tiny panties, and rubs his cock on your moist pussy. You look at him pleadingly, wanting his hard cock in your tight new pussy. He obliges, as he slides his cock inside of you as you feel an immense wave of pleasure and pain from your 12 year old virgin pussy. You grind your hips up against his to get the full length of him inside you, and you moan like crazy, love every inch of him. You feel your pussy contract around his cock as you start to cum. He also starts to orgasm, and he fills you full of his cum as you moan from the pleasure of your own orgasm.
He pulls out of you, pulls his clothes on, and walks away as you lay there on the ground, naked and dazed.