where Black Hat is an active villain and Demencia is an active superhero, both created by Flug who tries to stop them both because they always destroy like half the city while fighting.
Imagine every time Demencia defeats Black Hat, instead of normal jail they send him to her so he has to spend time with her because that's the worst kind of torment to him.
Imagine everytime it seems like Demencia killed Black Hat she panics and tries to heal him while repeating "I'm sorry, I'm sorry, I'm sorry" over and over again.
Imagine them having to join forces and getting to know each other better with time through moments when there's need for their different abilities or when their enemy spills some of their tragic past. Imagine them fighting in day and dating at night, going to small restaurants and laughing at stupid jokes, and then going back to their enmity.
Imagine a new superhero coming to help Demencia or a new supervillain helping Black Hat and them desperately trying to sabotage this "helper" because they fell for each other and don't want to kill each other.
Imagine one of them saving the other and the whole world gasping because it was in TV and the whole internet community and especially Tumblr going crazy over how they KNEW this was going to happen and normal people judging Demencia for loving a "bad person" while all the villains and criminals judge Black Hat for even being able to genuinely love someone.
Imagine Flug contacting them and hiding them until the world calms down a bit, meanwhile they think up a plan to get back to work - they pretend to betray each other and hate each other even more, now fighting with Flug's gadgets and still meeting at night.
Imagine one day Demencia gets shot and is in critical condition and Black Hat goes berserk trying to find the person who shot her, turning the whole city upside down searching, and then brutally murdering the guy but when Demencia heard this, she gets super upset about it, stands up from the hospital bed, marches across the room to Black Hat and scolds the hell out of him, but then her body remembers it's still almost dead and she collapses.
Imagine Black Hat being afraid to visit her again so he stays away and one day she just kicks down his door and brings him to jail and everything is back to normal because again he is forced to stay with her but this time he's fine with it and actually enjoys it and Tumblr just d'awws when they see it.
Imagine the author of this actually writing a story instead of putting it up like this.