All you have to do is heap compliments on her when she's doing the deed. After she feels like a world class cocksucker, and you've told her how erotic it is to see some dribbling down her chin, you won't have to worry about getting caught. It's easier to explain why you couldn't help it due to her tremendous abilities and ask for forgiveness.
Or you can just walk up and shoot her in the face while she's watching Dr Phil.