Emo fashion, lifestyle, and music has been thriving longer than it gets credit for. Although it is now mainstream...once again...it never stopped being a lifestyle for many of Marvel's infamous villains. Whether through their dress, which is a minimal reason to consider, their pasts are ridden with both internal and existential drama.
The emo lifestyle is not always exponentially pervasive in this regard, obviously. When it comes to Marvel villains, however, it is. If someone is going to play 'Black Parade' on a loop, it's these guys. These guys are the negative stereotypes, not the trendsetters nor the rule.
7 Morbius
Dr. Michael Alexander Morbius' entire being is the definition of an emo phase. For starters, he is a biochemist. Even more so, he is a biochemist with a problem. What is worse than that? It is a rare blood disease. Worse than that? He tries to cure it and in doing so turns himself into a vampire. It is also worth mentioning that he lived in Greece for a time.
A place that is notorious for its tragic heroes and villains. He basically grew up surrounded by historical angst and the floundering tourist industry. Michael also has daddy issues. His dad was an artist who was never around. His dad also made surrealist films. Which just screams malaise. Morbius manages on his first day as a vampire to kill his best friend too. Not to mention many Marvel fans consider him to be a misunderstood villain. He was even engaged once. Thus making him heartbroken too.
6 Lady Deathstrike
Yuriko Oyama's existence has been an incredibly challenging one, to say the least. Apart from an abusive father (the supervillain Lord Dark Wind) and losing her fiancé in a horrific way after liberating him from threatening circumstances. On top of that, her dad manages to have her brothers killed after creating a cult of assassins. Her fiancé, by the way, was one of these assassins, who she fell in love with and tried to steer away from her father's syndicate. She succeeded and manages to kill her father, but the end result left her fiancé killing himself because the loss of his master was too great. Naturally, he had more love for Lord Dark Wind than Yuriko.
She didn't take any of this well. Rightfully so. She also gets a bit miffed when she finds out that Wolverine is walking around Canada with an adamantium skeleton...that which she believes was the result of her father's life work. What does she do? She finds the sorceress, Spiral, and gets transformed with a machine body and her own set of adamantium claws, because she wants to be prom queen too.
5 Venom (The Hostless Symbiote Part)
The symbiote, known as Venom, before finding a host had a very lonely start. According to it, it was created by an elder god called, Knull. Venom didn't like to be told what to do, by Knull and thus became ostracized by Knull and other symbiotes. The poor fella wandered alone until he was discovered by Kree explorers who wanted to bond him to one of their own, a soldier by the name of Tel-Kar.
Tel-Kar didn't want to be a part of Venom's life anymore and separated from him. Venom later found a new alien friend with who he bonded. The alien wanted to use him to take out his species. So much pain for the symbiote outcast. All he wanted was a friend because he was lonely.
4 Loki
A god of mischief, and raised as a prince of Asgard. Surely he had it all. Alas, it was not all fun especially constantly living in his brother Thor's shadow. Only to find out he was adopted. Not just adopted, but abandoned and left for dead as a baby. On top of that, his parents Odin and Frigga lied to him about it all. To protect him.
The nerve. Plus his sad past, he managed to grow up and become a powerful emo sorcerer and makes it his mission to make trouble for his adopted family. Not to mention he thrives on drama. Doing good or bad depending on what swayed him as to what was the most interesting thing at the moment. Creating unnecessary and inconvenient spectacles is what Loki is best at, after all.
3 Pyro
Like many of the villains on this list, St. John Allerdyce had an emo phase pretty steadily throughout his life. Sure things were hard for his career starting out in his youth working various odd jobs. However, he did get to find his "bliss" while traveling. He became a journalist and then was inspired to write novels. He was living his best life writing epic romance novels. It sadly was not enough. He fell in with the Brotherhood of Mutants.
Simon Lasker's version of Pyro also has an arguably Emo and distressing past. In his youth, he managed to burn down his school and was an easy recruit for the Brotherhood of Mutants who used pain to win him over. Whichever way fans of both fire manipulators want to go, either one has a sad tale to tell.
2 Hobgoblin (Phil Urich)
Phil Urich was initially a promising journalist at the Dailey Bugle. His luck ran out while taking part in an investigation at Oscorp Tower and becoming exposed to the goblin formula. However, unlike other past villains, Phil wanted to use this newfound power for good. He was even friendly with Spider-Man and would lend him a hand from time to time. Unfortunately, Phil started to have adverse reactions to the goblin formula, much like some of his predecessors...and...well...he went a little nuts. Sadly he became a psychopath and his emo villain story began. Apart from murdering people and almost killing Spider-Man; Phil's extracurricular activities involved breaking up a couple and stealing the guy's girl. He also managed to attack Spider-Girl when she made him feel insecure once.
1 Blackheart
Being the son/creation of Mephisto has to be a hard time. He was created by the evil and murder vibes of various citizens in a town in New York. With so many expectations to live up to, there is just a lot of pressure thrust upon, Blackheart from the very start. Mephisto (dad) was always disappointed by his son's failure to mind control various heroes and corrupt them. He must have felt lonely. Not to mention he has literally been to Hell and back again. Mephisto even sent him on a field trip during his "evil training" with his powers depleted, so he could learn the concept of humility. Sadly, Blackheart's daddy issues did not stop there.
After several more failings, Mephisto cast Blackheart out of Hell without his powers and left him stranded on Earth. While there he managed to stir up more drama and conflict after trying to start a casino business, then trying to kidnap his own sister, and challenging the Avengers. This could have been avoided if he had just gone to his guidance counselor and found a better outlet to help him work through his many frustrations. Fans can't really blame him though, sometimes being a villain is complicated.