Actaully might as well toss the idea I am playing with her.
It goes off of Unicorn lore and how they only show themselves to virgins, basically she can literally sense who is a virgin, and knows where they are at, the whole time(within reason)
Not sure if the two main characters are virgins but thats how I'm playing it XD
Basically she feels safer with virgins, being one herself. Plus this allows for some interesting NTR where she knows she's being watched. Though you could have fun with it like Stoop Gallents did where the joke is that its all based on technicalities and vaginal sex is the end all be all for "being a virgin"
Eitherway have fun!