"So what is it that you guys, uh... do?"
"Oh, do not be coy with me, Avatar. Thou dost know very well the purpose of a unicorn. We are foolproof virgin detectors!"
"That is correct. So sensitive are members of my race to all forms of sexual energy that we can only tolerate physical contact with one who has not yet had any experience in that form of procreation - or recreation, if thou dost prefer."
"Yes, I find it most unpleasant to actually come into physical contact with anyone who is not a virgin, and I will avoid doing so whenever possible. Yes, well, I did not wish to get this personal with thee, but if thou does not mind, art thou a virgin?"