I first heard of asexuality when I was a teenager, reading an advice column, I think. To be asexual seemed to naturally have no interest in sex, in any way. Not sure if my impression of it has changed. It just seems to be absence of a sex drive (I could be wrong). My first thoughts were, "Oh that's interesting. I wonder if anyone I know is asexual. I wonder what it's like. Do they just stay single?" Some questions would include the last one, if people who are asexual stay single more often than they get in relationships. Is sex okay or do they dislike it? Also, when do they realize that they are asexual?
Also, someone in this thread said the Virgin Mary was asexual, which I believe is incorrect. After the immaculate conception, she had plenty of other children besides Jesus who were conceived sexually. She was a married woman, after all. Just wanted to throw that out there.