She covered his car in tampons
This Reddit user gave the following advice after finding out her boyfriend was cheating: “Attack his car with pads and tampons. Unused, of course. Don’t stick the pads to the paint because that will really mess it up. You don’t want to do any real damage. Tie tampons to door handles, windshield wipers, and mirrors. Find places to hide them where they won’t be found for a while. Pads stick well to windows. Guys will apparently freak out if you use a blue marker on them. I don’t know what they think periods are, but the one time I’ve done this, they thought they had been used. Because they were blue. If you’re lucky, it will rain right after you do it (so everything expands) and he’ll return with his new gal pal and be so freaked out that he makes her clear off the car.”