NSFW Fantasy'ing, Young Characters At School Scenario, Soft Blackmail?
Imagine: you spot your classmate reaching below their belt behind the bushes during recess, and sneak up close enough to see they've got photos of your bare butt on their phone!"Hey, where'd you get those pics of me!! Y'better delete em!"
Only for them to reply "You were mooning the whole class through the window the other day! I'm amazed you didn't get detention....I'll delete em if you blow me!"
"Oh...."