There are many ways to show just how evil a bad guy is. They may take great pleasure in their evil actions, do their plotting in not very lit areas, and like to put wicked cool spikes on everything like their costumes, their weapons, their Booby Traps, their toasters, etc. Simply put, they absolutely adore being edgelords, to the point of having a Bad is Good and Good is Bad mentality.
What other "evil" trait can you add to your cartoonish bad guy? Why, have him treat everything remotely smelling of diabetes — which may or may not happen to be everything coming from those do-gooders' Arcadia — as if it were toxic waste.
Anything that comes across as adorable, such as sunshine, lollipops, rainbows, puppies, and everything else that comes out of a Sugar Bowl generally tends to elicit a wide range of negative reactions from many Obviously Evil villains. Edgy, spike-wearing fiends usually harbor intense hatred towards the saccharine, and will not hesitate to grab a bat and beat a sack of kittens to death on sight, or at the very least make their lives miserable with dreaded finger pokes of evil. Sometimes, they may initially look charmed by said sack of kittens... right before bringing down the bat.
In other cases, villains may find cuteness just as completely revolting as people would normally find canned cheeseburger to be, (Yes, canned cheeseburger exists, and we suggest you don't Google images of it for the sake of your sanity and stomach contents) or even have a crippling phobia of it, running away screaming like they just saw a tarantula skittering towards them. For those unfortunate enough to live in a Sugar Bowl, whether out of circumstance or as punishment, such an Ironic Hell can completely drive them into insanity. While this trope is generally Played for Laughs, serious examples of this trope may lead to a Sugar Apocalypse in an attempt by the villain to turn the place into something more palatable, such as a Crapsack World.
Villains' reasons for hating or fearing cute things may vary. Their aversion towards cuteness may simply serve to indicate their evilness; if Hitler hates sugar, therefore sugar is good, for Hitler hates seeing people happy, and sugar brings smiles to sweet, innocent children and double the frowns to nasty, evil Hitlers everywhere. And besides, Evil Is Cool, so anything that Tastes Like Diabetes threatens to undermine their cool, villainous appearance and make them look lame. Card Carrying Villains, especially these guys, will do everything in their power to prevent this, and deviating from their ways by falling under the influence of cuteness may lead to being told, "If You're So Evil, Eat This Kitten".
Sub-Trope of Bad is Good and Good is Bad, and a common characteristic of Cartoonish Supervillainy. If the "cute" is directly weaponized to fight evil, see Care-Bear Stare and Super Cute Superpowers. If evil is repulsed merely by the presence of cute, see Too Spicy for Yog-Sothoth.
- In Deadman Wonderland, sociopathic Fake Cutie Minatsuki is greatly perturbed when she finds herself petting an armadillo.
"You little fucker, why are you not uncute?"
- Dragon Ball: Frieza is a tyrannical, absolutely sadistic Evil Overlord who enjoys massacring entire races and feeling superior to those he conquers. His ironic, personalized Hell after he died on Earth in Resurrection 'F' has him trapped in a cocoon hanging off a tree, surrounded by fairies, pixies, and stuffed animals dancing, singing, and frolicking all around him for eternity (At least until his henchmen bring him back to life, again). Predictably, he absolutely hates his punishment, and the scene is so saccharine it makes him want to tear his eyes out and traumatizes him long after he escapes from Hell.
- In a Batman / Judge Dredd crossover, The Scarecrow used his signature fear toxin on Judge Death, putting him in a hallucinatory nightmare pictured above where the demon judge is tormented by his greatest fear: Fluffy bunnies, pink unicorns, cute Woodland Creatures, and Happy Puppets.
- De cape et de crocs: Mendoza's Motive Rant shortly before his Karmic Death has him go on about how he hates Eusebe for... basically being a cute little rabbit.
- The Mr. Men fan story ''Little Miss Wubby'' has Mr. Uppity, Mr. Grumpy, Mr. Rude, Mr. Mean and Mr. Grumble all hating cute things to the point of wanting them destroyed and when they meet the sickeningly cute title character, they all gang up on her and drive her to tears. They end up paying for it when a few of her friends snuggle and hug them.
- My Little Pony: The Movie (2017): When the Storm King invades Canterlot, one of the first things he does is complain about how cute the appearance of the castle is, on account of it clashing with his big, bad powerful guy image.
- Star Trek: The Original Series: In "The Trouble With Tribbles", Klingons react to Tribbles with hostility and disgust just as surely as Tribbles react to them with hisses and screeches.
- Fairly OddParents: The Yugopotamians are introduced as an evil alien race with interest in things like violence and garbage. However, they are absolutely afraid of anything cute and cuddly.
- Phineas and Ferb: Self-proclaimed evil-scientist Doofenshmirtz hates...well, a lot of things. One lyric from "I Really Don't Hate Christmas" states:
I hate puppy-dogs and kittensI hate flowers in the springHeck, I even hate the sunshine, and the birdies when they sing.
- Plankton from Spongebob Squarepants considers himself to be a Card-Carrying Villain who gags at the sight of cuteness. When he enters Spongebob's brain in one episode, everything there is too cute for him to stomach.
- When the Butt Witch first emerges in Twelve Forever, her first reaction to seeing the Endless Island's Sugar Bowl nature is to wince in disgust, her dialogue implying that it was originally a Crapsack World that she - an Emotion Eating Humanoid Abomination Made of Evil - ruled over before Twelve turned it into the Never Land it is now.
Butt Witch: THIS IS REPULSIVE! Wrong! This is all wrong! What a horribly tacky place this has become! Everything is so trivial... and cute!
- Gargamel from The Smurfs hates springtime because that's when the birds come back from migration, the flowers bloom, and there's more sunshine. He also thinks the Smurfs themselves are disgusting.
- Ultimate Spiderman: Seems to be the case with Juggernaut, if his reaction to Squirrel Girl's "army" is any indication.