As soon as he feels the fangs slide out from the holes they had created, Mettaton shudders. A hand comes up, covering the holes so as to stop any excess blood from dripping out. He whirls to shoot the man a cold look, but that doesn't turn out to be such a good idea.

Maybe Liquid hadn't drained him excessively, but it was enough to make him a little bit disoriented.

"Intense...right," he says curtly. "As if being human is not intense for me, thank you very much for taking advantage of it..."

Although he's acting annoyed, there's a rush of color in his cheeks. No way he would ever admit he enjoyed the prick of pain and the sensation against his neck, of course. Well--He wouldn't dignify it with words.

That's his business.