Hudweiser has a vengeful streak and never forgets. When I was 6-7ish, a 'friend' of mine with a bizarre fetish for car accidents stole some Matchbox cars out of my schoolbag and stomped on them before just putting them back for me to find, even showing me his handiwork with a smug grin. Some years later when we weren't really friends anymore, but not enemies either, I was happening by the Home Ec lab where he was in a class making lasagne just as they got sent off for recess. Nobody was around, so I idled in, poured an entire uncooked lasagne into his bag, shook it around, and made sure it seeped out over his jacket on the chair, and left. No culprit was ever positively identified.