Vivia tries to escape.

With the last bit of energy she could muster, Vivia brought her unbound legs forward and attempted to rise to her knees. Abruptly her back met the centaur's underside, and she once more fell down onto the stones, knocking the wind from her again.

He noticed her movement, and rushed to penetrate her before she could get up again. In his haste, his cock slipped into her undergarments and prodded her asshole, repeatedly pushing against it and smearing it with fluids before it finally managed to enter her.

Vivia cried out with what breath she was able, and gasped as the thick head of his member penetrated her rear. The centaur rutted into her ass slowly, leaking enough fluid to let him get deeper inside her with every thrust. Her mouth hung open, squeaking moans escaping her as he managed to slide a good few inches in.

Vivia gasped and grit her teeth as the centaur filled her, stretching her wider than she thought possible. She had never slid more than the tip of her pinky in there, and now she was being anally fucked by a beast of a cock. On top of it all, despite being bound and bent over in the dirt, she found herself feeling a primal pleasure during the sordid act.

As she was rocked forward rhythmically, Vivia groaned in time with his rutting, the side of her face on the ground with strands of red hair falling before her flushed and freckled face. The centaur managed to slide back-and-forth an inch or so with each thrust, soon picking up the pace and making her let out a constant, ebbing moan.

It was dirty. It was rough. And it was fucking wild.

Finally, he came inside her ass, and the moment she felt the hot seed fill her bowels, she was pushed over the edge of her own orgasm, quivering and moaning with ****, sticky surrender. Vivia soon let out a shuddering cry as the centaur slid his thick phallus out of her with a sucking noise, dripping cum down across her cunt and thighs.

A mewling moan escaped her as she did her best to catch her breath, wondering if he was done with her yet. She was a mess, lain upon the dusty, dirty ground and bent over as she was, but dammit... she had never had an orgasm like that before, and was ashamed at the thought of wanting the centaur to stay.