In a certain popular manga-- points for anyone who can recognize the source-- a female character, having rejected a male suitor, sees him get dragged away by another female. First female remarks, "Knowing that he belongs to someone else-- makes him interesting."
Purely going on personal experience, do you think there is any greater covetousness in the female or in the male (assuming one can use such terms with impunity)?
Or if it's the same, are there still different factors in the motivation?