He lay Jenny on her back as the old man did but stuttered "You, you don't seem o be wearing any pants." Jenny giggled. "Sir, would I come to work not wearing pants? Of course I have something on -- it's my favourite g-string panty. Yes, it's very flashy sir but how was I to know I would have an accident sand end up on my back in front of an old man, a stranger?"
If what you don't know can't hurt you, she's invulnerable.