The first bit of dialogue is fine, and so is the second, but I can't say the last is very direct. That first "exactly" feels weird, though, I'd toss it out.
The last sentence is also curious. I know he's saying "Don't" since he's being teased by the Captain, but this isn't made apparent until the next paragraph. It feels like you forgot to add that the turian's coming closer and starting to tease the human. I assume it should go:>(...)He trailed off. The Turian extended a hand and grabbed at the human. "Don't," Jackson said softly.
Then later, in this next sentence:>But Nemaeus didn't removing the hand resting on his hip. The turian was inches away from him now, staring directly into his eyes.
should be something like>Nemaeus didn't remove the hand resting on Jackson's hip. The turian moved closer, and was inches away from him now, staring directly into his eyes.
Because it wasn't made exactly clear that the turian was moving a little closer. >The turian leaned down and in, nipping the human's neck and then licking with his bright blue tongue, making him groan
This should be something like>The turian leaned down, nipping at the human's neck and then licking with his bright blue tongue, making Jackson groan
Unless Jackson wasn't supposed to be groaning, then you can still have the "him" there.
I'm kind of surprised here, because what comes next is actually much better in comparison, but I wouldn't put tildes (~) in dialogue, or anywhere really. I had a note earlier saying you should look up how to use -ing words, but you seem to have a grasp of it later on.>it's a blast to work on it and be here tonight!
and to be here tonight
It still works either way, but it sounds a little strange. You can keep it if you want, because it's dialogue, and characters can say things that sound weird.>it was an obvious giveaway he was always intending to drop his pants
Gave me a good chuckle.
Seems pretty OK to me otherwise!