I gave a guy a pair of my panties in high school. He dared me to just take off my underwear. Since that could mean two things, I figured I’d take off my bra under my shirt and give it to him. However then the thought crossed my mind that taking off my panties would be way more risqué, and I was definitely in the mood to make some jaws drop.
I was wearing a dress so I just stood up and pulled them down. He seemed surprised so I handed them to him, told him that he could keep it as a reminder of the only time a girl would do that for him. Got a decent laugh out of the group with that one.