The reason for this definition is because the vagina being sexually superior to the male penis. And is also worshipped by men, weak and strong alike. So being a cunt is a high praise.
Also being called a pussy is quite the same as well.
You: Did you see that bitch the other day?
Them: I sure did, I should have beat her ass
You: Why didn't you?
Them: Because I made her man break up with her and take everything in the divorce.
You: Damn...you're kunt bitch
"He eats me out and I don't give anything in return...I'm hella Kunt"