Villanelle is a joyfully murderous psychopath assassin and Eve is the investigator trying to catch her who Villanelle seduces Eve into enjoying her own more murderous side. Villanelle does a Ton of murders (including of a tech bro billionaire), Eve also does some murders. It’s a good time.
Zhou Zishu is an assassin and spymaster who put the current Emperor on the throne, and then quit his job by faking his death (kinda, hes still dying but not as fast as he was supposed to). Had done A Lot on his old job, including murdering children (more than one, and at least one of them in a way I can't even describe without several trigger warnings), exterminating whole families, war crimes (and i dont mean this in a buzzword way, i mean "organized a public execution of foreign diplomats during war time")… btw he doesn't feel particularly bad about any of this, because he believes it was necessary. Like he wouldn't do it for fun, but he thinks the ends (putting a good Emperor on the throne) justified the means (all of the atrocities). As a retiree, he definitely cut down on the amount of morally reprehensible murder, but not murder in general. He still routinely kills ppl, he just doesn't go out of his way to kill more.
Wen Kexing, meanwhile, is the Ghost Valley Master - Ghost Valley being a place where the worst of criminals are exiled. Even in such a place, he has reputation as a complete lunatic, owed partially to the fact that he either skinned a man or fed him his own flesh or both at one point, and partially to him having a rule where he would kill anyone who came closer than 3 meters to him. But in truth, everything he'd done was to survive the Ghost Valley and eventually take revenge for his parents, who were brutally murdered when he was only nine. By the start of the novel's timeline, he put his plan in motion - the plan that would drown jianghu in blood, but also deliver poetic justice to all responsible for his parents' deaths, as well as all who'd commit the same crime given the chance.
And these two men, these two murderers and schemers, meet - and unexpectedly, find in each other the person who /understands/. The person who is just as ruthless and whose hands are just as bloody, but also the person who knows standing at the top of the world is not worth it, who seeks the same freedom of leaving it all behind, and who is still, underneath it all, a human, with human heart seeking connection.
So you have this couple who understand each other with barely a word, and who want the same things - who are so hungry for domesticity and for people they can just goof around with when all their lives they had to measure every step and word - but ALSO where one half a couple is like "i gotta go murder hundreds in revenge" and the other half is like "ok pick you up at 6". (This btw is why I'm submitting novel's iteration of the couple in particular. Show wenzhou with their ridiculous breakups over morality could Never.) Also they were both hiding who they are when they first met, and later flirted about having figured each other out.
Finally, I'll leave you my favorite quote that just. perfectly sums up their relationship:
"And just like that, they fell asleep in each other's arms, steeped in the smell of blood."
You’ve probably already had submissions for them but I’ll add on. One of them founded an assassin’s guild and killed a staggering number of people. His malewife is the leader of a sect of insane murderous outcasts, and he attained his position by proving to be the most crazy and murder happy of them all. Most of the plot involves him wandering around watching his schemes get more people killed. Together they adopt a kid that was only orphaned due to said scheming (oops). They’re terrible and I love them.
