Womanizer is a guy who gets every girl to like him. a gutless and senseless man who treats every girl like they’re the girl for him, then lets them down by having MANY other girls on the side.
A womanizer is compared to an onion because he generally uses layer after layer of sweet words and other deceiving tactics to seduce a woman. But in the end, the romance comes to nothing, leaving the woman in tears when she finds out the truth.