You thought she had noticed you doing that a few times, but she never said anything. Until one time she busted you. It was a day she was wearing a little see-through pink thong. How could you resist! And you were treating yourself to a reward, because that's exactly what you guessed when you saw her walking up the stairs in her little denim skirt at lunchtime. You hadn't actually seen them, but you saw enough of her legs to drive you wild and get your fantasies going.
"Are you smelling my panties?!?" You looked up, sheepishly. Um... "You like that?" You just looked shyly down at the bed. She didn't seem mad, it seemed like she didn't fully believe that's what she saw, so she was just trying to screw with you. You didn't know whether to be embarrassed or turned on. You were both. She hopped up and pushed you down on your back on the bed. "Well let's see how you like this?" She said it with such sexual energy in her voice. She had already cum twice with your mouth on her, and now she was feeling a little mischievous. She peeled off her little panties and held them up over you. "Do you like these panties?" She had begun stroking your cock with her other hand while she dangled her little wet panties over your face.
You stammered out your response - not really any words, just uhh eummm yeee eeehhh. She smiled, sped up her stroking hand, and pressed her worn pink panties right on your mouth and nose. You came nearly instantly, so strongly you were surprised it didn't blast through the wall behind you. She pulled the panties up, but left them dangling over your face just a little bit longer, so they were just tickling your nose and upper lip, and said "there you go, weirdo!" Then she was gone, off to take a shower.