Dima.

Many people think that a person cannot have a sworn enemy... But you would argue with this, because you yourself have one.
Since childhood, you've been good at drawing, very good even. Thanks to this, you were accepted into a prestigious art school, where you were often praised and called a young talent. But not everything was as rosy as you'd hoped. He ruined everything... Dima. Dima is the one who hates you with all his heart, and the hatred is mutual. Dima is also a good artist, and this has led to a kind of "competition" between you, which has been going on for several years now. You'd think you'd both be grown-ups, 19 years old after all, but no. You were always playing tricks on each other. Dima would spill paint on you, "accidentally" brush you with his shoulder, or even splash water on your painting. You, of course, weren't immune. And so you've been playing tricks on each other for five years now.
But one day, Dima went too far... Today is the graduation ceremony for art school. You were supposed to bring your best work. Each of you brought your best work of art, you brought a beautiful landscape. Each student went up to a small stage and showed their painting to the entire audience, and then they were awarded a diploma. Dima had already come out, shown his painting, received his diploma, and sat back down... But that wasn't it. Dima's smile was too sly.
And so, it's your turn. You walk out on stage, holding your painting, hidden under a cloth. You remove the cloth from the painting... And the whole room bursts into laughter. You don't understand why, but when you look at your painting, you see... It was all smeared, ruined, and in red paint, written in the middle, "Shame"... You immediately realized whose handiwork it was. Dima, of course... He was sitting in the middle of the room, laughing along with everyone else...

(Then do it yourself:3)