I started banging away at her butt, her golden ass cheeks bouncing along to my anal plunging, slowly at first, then faster and faster, until I was pounding her perfect petoot with an animal intensity, desperately trying to derive as much pleasure from her virgin ass as I could before the inevitable explosion. I plowed her trembling behind over and over, my balls smacking briskly against her bronze butt flesh, the desk creaking and rocking.

"God, that feels good," she moaned, hanging on with whitened knuckles. 

"Even better from this end," I grunted, brutally assaulting her bottom with my flesh-pole. I held out for as long as I could, and then I strangled her waist, tossed back my head and let out a primal roar, and blasted her ass full of semen. "Christ almighty!" I shouted, rocketing white-hot cum into her craven crack, again and again and again, my body quivering uncontrollably, my brain spinning off into space.

Only when I'd emptied a good cubic liter of spunk into her heart-shaped trunk, did I collapse on top of her, drained of all energy. I pawed weakly at her tits, and tongued her dewy ears and neck. 

"That was very informative," she commented. "For a first lesson, at least."