Women Really Would Kill Men for Hitting on Them Wrong

 ...but they don't understand homicide, so it doesn't really count. 

 Yes, a woman would absolutely kill you for hitting on her when she doesn't want you to, to prevent you ever doing it again. However, she doesn't understand the value of life - even if it's her own kid, she still doesn't understand, because she puts it too high. 

 A man at least vaguely knows that if you kill someone a) he might fight back, you might lose and b) you're apt to start a blood feud, the rest of their family* is like to come after you. There are costs that must be paid, so it shouldn't be done on a whim.

*(Unless Anglo.)

 Women think killing a man is free, they just realize they can't even though they want to.

 You can try to explain it to a woman, but it's all "What would you feel like if you hadn't eaten breakfast this morning?" 

 "What would you feel like if someone killed your son for flirting wrong?" "But my son would never flirt with me - he's my son." Absolutely can't even. 

 Generally, this is in fact more correct. You should indeed value the lives of strangers at approximately 0. However, women make it a narcissist moral imperative. "I don't value this life, therefore nobody is allowed to value this life." To a woman, [stranger] is an absolute term, not a relative term.

 This is one of the ways to sell 'patriarchy' to women. Strange men stop them from having random annoying men killed - oppression!!!!1!! See? "He tried to stop me from killing this nervous nerd! That rapist!" Anti-homicide laws are immoral violence. Of course very few women are dumb enough to admit this reasoning out loud. It's one of the reasons feminism sounds so dumb - they're just lying, and making stuff up on the spot is not exactly a core competency. 

 In a woman's mind, men are of course omnipotent. They can't afford thinking more complex than [more powerful = all powerful]. (And not coincidentally [less powerful = completely powerless]. Binary thinking.) They think men could make a world where women could kill failed casanovas, and men aren't doing it out of sheer misogynistic spite. Most of the time they don't even understand the awkward flirt is still strong enough to kill her himself if he really wants to.