Tessa,

This is very well done. I do believe it's gotten quite hot in here.

I have a few nits, but they are more for you to check the sentence structure than anything else.

Always thinking ahead, I had sharpened the knife very carefully before leaving home, and was well aware of the damage I could inflict. With a growl, my legs forced hers apart even more. Sliding the blade down the side of her hip, I admired the way her flesh yielded beneath it. I smelled her fear. It snaked up between us and sliced into me as deeply as my blade could into her flesh. I wanted to cut her, to watch her bleed, and craved to see those ribbons of red on her pale flesh. My urge to cut was every bit as strong as my urge to fuck, but this wasn’t the time. Not this time…
...

Pushing myself on top of her again, I moved the knife to my other hand and again - remove "," - slid the blade against her flesh and under the fabric. - Remove "It was" - Like cutting into warm butter, the fabric fell away. I closed the knife and replaced it on the stand. Reaching under her, I fisted the scrap of material and pulled it away. As I did, she attempted to wiggle away from me. With the intent to overpower, I dug my fingers into the flesh of her hips and flipped her over onto her back. Using moves I’d learned long ago, I held her there, keeping her immobile. She struggled against me. Her breath came in panting spurts, more from the fierce excitement than the struggle. I brought the now useless panties up to her face and shoved them partially in her mouth. She twisted her head to the side, trying to avoid getting an entire mouthful. She made a pretty picture, lying there beneath me, with her pink, cut-up panties filling her mouth.
...

See? It's really minor stuff, those last itty-bitty edits that need a bit of tweaking. And, in reality, if you were going to publish this piece for money, an editor might be assigned to catch those few items.

Keep up the great work, Tessa and write on!

Ruby