Actually rather appropriate. The unicorns of classic myth were, despite their majestic appearances, rather monstrous. It took a virgin, a "living symbol" of purity, to calm it. :P Clarification translated from one of da Vinci's notebooks: The unicorn, through its intemperance and not knowing how to control itself, for the love it bears to fair maidens forgets its ferocity and wildness; and laying aside all fear it will go up to a seated damsel and go to sleep in her lap, and thus the hunters take it.