He wasn't certain as to why she laughed, but just as easily assumed that it was because most people tended to laugh whenever he had something to say. Normally, he would have made himself clearer, but he was aware of the game he was currently playing.
"I have no way of knowing," he replied. "I've only been here a single night. But if this is a different planet, then I have every reason to suspect that everything here is alien in nature. If you're so desperate for blood, we can find the necessary equipment to transfuse some of mine. Having been bitten in the past, I have no desire to experience it again."
It felt unclean to suggest such a thing, but he didn't see how anyone had a choice. It was important to form alliances and clearly, she was aware of him on some level. If she was aware of him, then he supposed either Dean, Jo, or Mary had already threatened her. That would not have been surprising.
He eyed the nurse warily, but then his eyes traveled back to her. She likely knew of what he'd have to do if she refused.