[Spoilers for Get Out and Stranger Things below.]

The concept of a "good villain" is inherently paradoxical. After all, a villain is a natural foil for the hero, a diabolical antagonist who operates in complete contrast to the good and moral protagonist. But there's something to be said for a captivating villain who can cast a shadow over an entire room.

The nominees for Best Villain at this year's MTV Movie & TV Awards are just that. In Get Out, Allison Williams plays a privileged white woman with malicious intentions, while Jared Leto dove headfirst into The Joker and delivered a polarizing portrayal of the psychopathic Clown Prince of Gotham. Meanwhile, the fearsome Demogorgon terrorized the cute little kids of Stranger Things, and Jeffrey Dean Morgan made one of the most controversial and stomach-churning entrances ever on TV as Negan on The Walking Dead. As for Wes Bentley, well, he just scared the shit out of audiences as the Pig Man on American Horror Story: Roanoke.

But what makes a bad guy, really? Dr. Robin S. Rosenberg, a clinical psychologist and author who specializes in explaining how superheroes relate to our own psyches, defines a villain in relation to the hero.

"We know from any kind of fiction that the protagonist or the hero is only as heroic as the villain is villainous," she told MTV News. "The villain has to challenge some aspect of the hero's character, strength, or integrity in order for the story to be compelling."

Take The Joker, for example. Perhaps the most famous Batman villain in the comic-book hero's 78-year history, The Joker is a textbook psychopath. It's important to note that psychopathy is a personality construct defined by a person's lack of empathy and not a diagnosis of a mental disorder. The Joker may be a sadistic bastard but he's not suffering from any symptoms of psychosis. In fact, he knows exactly what he's doing, which makes a guy like him so menacing. Look no further than his pathological need to control Harley Quinn for even more proof of his psychopathy.

"The Joker literally weaponizes mental health stigma, as exemplified by his choice of electroconvulsive therapy paddles to torture Harley," Dr. Vasilis K. Pozios, a forensic psychiatrist and cofounder of Broadcast Thought, said. "He's making literal peoples' misunderstandings and fears about mental health and treatment."

Yet for all of his ludicrous misdeeds, the character is insanely popular among comic-book aficionados and fair-weather fans alike. "The unpredictable, pure sadism of The Joker is very frightening. That's part of his appeal," Rosenberg said. "Superheroes are predictable, and even most villains are predictable, so that idea of an unpredictable villain who knows no bounds, who literally operates outside the normal boundaries of villains, is intriguing."

Negan is another character who exhibits that kind of unpredictability. The character's formal introduction at the start of Season 7 was lambasted for its brutality, but his ruthless ideology and unnerving charisma have since made Negan a fan-favorite. His erratic nature, however, remains his most malevolent trait, especially given his authoritarian power over the show's heroes.

"The showrunner wants you to feel that uncertainty of this guy who can make these big choices, like who lives and who dies," clinical psychologist Brian Kong told MTV News. "Part of what makes him scary is how casually he makes those decisions."

According to Kong, Negan represents more of a dictator, or "someone who sees themselves as very special." More importantly, he's someone extremely skilled at getting people to follow him. He's similar to a cult leader in the way he indoctrinates his followers. They can either adopt his philosophy, or be killed. Kong goes on to clarify: "He's driven by a bigger goal. He wants to win. He wants to accumulate and survive, and he wants to rule. These dictators are driven by this narcissistic motivation. They're very vindictive, and there's this grandiosity about them."

Negan, like all of the characters nominated for Best Villain, show some of the diagnostic criteria of an antisocial personality disorder. No, this doesn't mean the Demogorgon doesn't want to socialize with others at a party, but rather that it, and the others in this category, shows a lack of remorse for its actions.

"Antisocial is the personality disorder that murderers have — lying, deception, failure to obey laws and norms, lack of remorse for actions, aggression, [and] a disregard for the safety of others," Kong said.

Williams's character in Get Out, in particular, shows a lot of these signs. Part black-widow killer, part "woke" white woman who weaponizes her whiteness, Rose knowingly lured Chris into her trap. "She seemed to be the most intentionally manipulative and deceptive," Kong said. For example, when Rose deadpans, "You know I can’t give you the keys," after just frantically searching for her car keys for several minutes, that's exemplary of the lying and manipulation associated with an antisocial personality disorder.

"Oftentimes it's for their own amusement," Kong added. "These are the people that kill cats when they're kids."

Of course, just because Rose shows no remorse for betraying Chris doesn't mean she's completely apathetic. "Is she pure evil, or is she someone who's been indoctrinated into this cult?" Dr. Praveen R. Kambam, a forensic psychiatrist and fellow cofounder of Broadcast Thought, asked. "She might be rationalizing her actions in her head. She might have feelings for people, like her family." That only makes a character like Rose more unsettling. She's the character we're meant to relate to, but in reality, she's just a psycho who keeps her colored Fruit Loops segregated from her milk.

"Wondering if you're the villain is a pretty scary thing," Dr. Pozios said.

The Demogorgon is neither human nor particularly interested in cats, but what this predator represents to audiences is the unknown, and by association, the fear of the unknown. Kong explained that the Demogorgon itself could be an allusion to Swiss psychiatrist Carl Jung's concept of The Shadow, or the "fear and fascination with the unknown and dark side of ourselves." He points to a popular fan theory that Eleven and the Demogorgon are one and the same to suggest that the Demogorgon could be a "physical manifestation of Eleven's fear and trauma."

In addition, Dr. Pozios postulated that the Upside Down could be an allegorical representation of "how somebody with depression might see the world." He adds, "It's the same world but more bleak and hopeless."

If the Demogorgon is the physical manifestation of darkness, and Eleven is the light, then ultimately Stranger Things ends on a hopeful, albeit bittersweet, message. Light triumphs over darkness. Good prevails over evil. And the kickass young heroine with telekinetic abilities will always slay the monster.

"As Americans, we like all of our films to have a happy ending. We get upset when they don't," Dr. Rosenberg said. "There's a comfort in predictability ... We know that the superhero will be victorious, and if there is some ambiguity, we know that it's just setting us up for the next installment."

Be sure to tune in to the 2017 MTV Movie & TV Awards on Sunday, May 7 at 8 p.m. ET/PT. And check MTV News for all your updates on the big show.