I know I have a case of "murder hot" in an intensity usually found in women who write love letters to serial killers (though I stricly limit myself to fictional murder being hot). However.
Imagine. You have a protagonist who is a famous villain, a notorious criminal, extremely dangerous. You introduce a young woman, who immediately starts outrageously teasing him and flirting with him, and it eventually becomes clear that he enjoys her presence, plays off against her really well, they get along like a house on fire. Turns out, the woman has a dark secret - she had to leave her last place of residence because she murdered people. Mostly got away with it, too.
And instead of either a) letting him recruit her for his organisation or b) letting them fuck before they each go their own way, you decide that... the villain tells her sister that he will keep an eye on her so she doesn't ~give in to her dark side~ again? And then you put her in a relationship with the undercover cop supposed to find her (but she doesn't know that part!) bc she wants to start over and be good? Which the villain encourages? And when the cop's superior comes and wants to arrest her... she is shot dead while... not going for her signature murder weapon, no, but for the baby clothes she knitted bc ofc she's pregnant from the undercover cop???
How do you ruin this much potential for some nice fucked up villainy and instead go the most boring (and conservative/conventional, not to mention lowkey sexist) route???