She might not have sex before marriage, but no girl gets offended if she finds out that men are attracted to her.
Thats true.
But when she hears the question "would you do her", she'd feel like some sort of commodity, some sort of thing thrown in the street just waiting for guys to do her.
If you asked me, would you find her pretty? Would you fall for a girl like her if you found out she was good looking, that would all be ok.
But the way you put the question might be ok in western culture, but its not ok here. Most girls would be offended by that here, and i am sure of this, its not something i am speculating about.
I'm sure you don't intend any harm. But i'm just giving you the heads up, if she's ever around, don't ask that sort of question about her in front of her.