There are many approaches an author can take to writing a compelling villain. In the DC Universe, the gallery of rogues is often made up of genuine sociopaths, apathetic monsters who delight in chaos. In the MCU, most villains are more empathetic, forcing audiences to ask themselves how easily they themselves could become the "bad guy".
Anime runs the gamut of villain types, but often these villains prove to be fan-favorite characters. While sometimes the likability of the antagonist is intentional — characters like Dabi, for instance, are bound to be sympathetic — there are some villains who by all rights should be loathed but remain adored all the same.
10 Sebastian Michaelis (Black Butler)
It must first be acknowledged that yes, Sebastian Michaelis is a handsome devil. But he's a devil all the same, and the face Sebastian presents is only a facade. In the midst of the series, fans seem to forget that Sebastian is a demon who wants nothing more than to devour Ciel's soul.
It's a testament to his characterization that fans choose to see Sebastian as alluring and devoted rather than evil. Logically, he's a monster, but aesthetically? He's a catch.
9 Envy (Fullmetal Alchemist)
One of the most devastating moments in both Fullmetal Alchemist series is the murder of Maes Hughes. While Roy takes his revenge on Lust primarily, it's Envy who deals Hughes's fatal blow. Envy hates humanity more than any of their siblings, so why is it that Envy remains a fan-favorite? Perhaps it's that deep, obvious hatred that actually humanizes Envy. Like their namesake, Envy is at times deeply ugly, but also painfully familiar. Envy is a jerk, but they're a jerk because they're jealous of that which they claim to hate. At times, Envy is altogether too real.
8 Toga (My Hero Academia)
Toga and Harley Quinn have a lot in common, and it's not just about the pigtails and moon buns. They both exude chaotic energy and winning charm despite their distinctly villainous behavior.
Toga is a vicious sadist who has no empathy for her victims. She uses her bloodsucking transformation quirk primarily to harm others. But she's also heavily informed by the yandere-character type, which many fans have come to love in recent years. Yes, Toga wants to kill Deku, but she also adores him. For whatever reason, that inspires a large portion of the fandom to adore her in turn.
7 Griffith (Berserk)
Is it possible that the same charm Griffith uses on friends and foes alike has also wrought its magic on audiences? Griffith is by all measures a truly loathsome character. A rapist and sadist, Griffith is a monstrous man who just happens to be eerily beautiful to boot. Over years of character development, he has only become a more clearly despicable antagonist. But Griffith remains a memorable, especially cunning monster, and his humble origins and dedication to his goals, however evil, make him compelling to watch.
6 L and/or Light Yagami (Death Note)
It's a matter of perspective, which of these two leads is the primary antagonist in Death Note. Both are despicable and likable at once, and this compelling contradiction has fueled the series' popularity for years. There are those who support Light's attempts to rid the world of evil people, and those who support L's pursuit of justice. And both characters are clever, constantly trying to outwit each other in a cat-and-mouse game reminiscent of the rivalry between Sherlock and Moriarty. There's something eternally satisfying about watching a pair of narrative foils butt heads.
5 Izaya Orihara (DRRR!)
Everyone knows that Izaya is holding Celty's severed head captive on his bookshelves. He pulls knives on his enemies and also pulls all the strings behind the scenes in the underbelly of Ikebukuro. He often hints that he's some kind of immortal being and not just a pain in the arse, and it's clear as day that Izaya Orihara is a sociopath and perhaps the biggest monster in a series filled with them. So what is it about Izaya that makes him so beloved? Terry Pratchett introduced the word "char-isn't-ma" into the lexicon. It describes someone so unlikeable and disturbing that you simply can't ignore them. Izaya has char-isn't-ma in spades.
4 Lady Eboshi (Princess Mononoke)
Lady Eboshi is a very proud woman, but she's not necessarily wrong about things. Ghibli is often praised for its nuanced depictions of female characters, and even if Lady Eboshi is the main antagonist in Princess Mononoke, she's a very likable character. She is a decent leader to the people of Irontown, and she values human progress and the rights of women. Unfortunately, this is often at the expense of the environment, which becomes her ultimate downfall.
3 Crocodile (One Piece)
Crocodile is, quite simply, one of the coolest villains ever to grace a shonen series. Former leader of a crime syndicate, the mafioso is one of the first characters to completely devastate Luffy in battle — twice.
It's hard to pinpoint what makes Crocodile such a beloved villain. He is a callous dictator with that trademark crocodile smile, and he doesn't actually care about his people. But he has charisma and even now, decades after the airing of the Arabasta arc, Crocodile remains unforgettable.
2 Hisoka (Hunter x Hunter)
There's no good reason why Hisoka shouldn't seem ridiculous. He's wearing clown makeup, and perhaps could be mistaken for an anime knock-off of The Joker. But fans of Hunter x Hunter know how very nuanced Hisoka is as a character. He's impossible not to watch, imbuing stage presence into anime as though it's theater. He's also spared the lives of those he feels will be better opponents in the future, a habit that could be mistaken as kindness. Even years later, Hisoka steals every scene he's in.
1 Kyubey (Puella Magi Madoka Magica)
Kyubey is a sociopathic soul-sucking monster, but boy is his design cute. Perhaps that's why he's featured on anime merchandise, existing in plushie, keychain, and backpack form the whole world over. Kyubey's evil only becomes apparent as the series progresses, and perhaps that adds to the likability of this fluffy alien parasite. There's something relatable about the fact that a smiling, cutesy face belies an empty heart. There's a difference between being "nice" and being "good", and Kyubey presents as benign simply because it benefits him.