This hot-as-**** 'straight' guy in my English class once tied me to a chair with his school tie and started massaging my shoulders, moving his hands onto my chest and abdomen and... further.
It was before the class had come in so they all just walked into the classroom to see me tied to a chair with this 'straight' guy (who's in the 'popular' crowd to make it more awkward) feeling me up

I had to pretend to be disgusted and appalled and while I wanted him to carry on I also wanted him to stop so he (and the rest of the class) wouldn't see the physical indicator of the fact that I was being aroused by it.