I'm probably treading on ground that has already been covered in this thread, but I'll add my thoughts just because of my narcissism and unwarranted feeling of self-importance:
A 23 year old male bangs a 14 year old girl:
1. A 23 year old male, in most cases, is not fully mature, and probably doesn't deserve the term "man"
2. He is a highly insecure fellow whose fragile ego is infinitely boosted by the awed admiration of the 14 year old. He chuckles at her a bit in his mind, and he tries to dismiss his attraction towards her, tries to talk himself out of it, but he just can't help but noticing what a cute little bod she has and soon she becomes the object of intense sexual fantasizing. The hard-on is getting the upper hand.
3. She finds him much more attractive than her male classmates, since it's well-established that girls at that age are usually a good bit ahead of boys of the same age in regard to emotional maturity. But, she is still not mature by any stretch, and her attraction soon turns into an all-consuming love drama in her mind.
4. So they have sex. For her, it is not so much an expression of horny lust as it is an honest, but misguided feeling of love, with sex being the ultimate expression of that perfect love that exists between them, in her mind. So when the sh*t hits the fan she will feel utterly traumatized and disillusioned. He on the other hand, knows going into it that he is playing this girl like a violin and he's being a very bad boy. But he is too immature, too flattered by her attraction to him to muster up the self-control needed to reign himself in. His hard-on is doing all the thinking, he knows it, and he surrenders to it.
A 23 year old female bangs a 14 year old boy:
1. She is probably more mature that her same-aged male counterpart, and is very close to being deserving of the term "woman"
2. She is flattered by the cute (and strapping) lad in her classroom that just can't take his eyes off of her. She tries to fight the fantasy, but dang he is so cute! She has enough experience with men to be able to read the signs, it soon becomes patently obvious to her that he is there for the taking.
3. The boy sees her as being hot, the ultimate, look at her man! He begins fantasizing about her constantly, though not in a "perfect love" kind of way. For him, it is pure lust. He is overwhelmed by his attraction to her, and she knows it and is flattered by it.
4. So they have sex. She, like the male in scenario 1 is overcome by her lust towards the boy, and knows that she is being a bad girl. She is driven wild by this cute and strapping lad that just can't get enough of her. He on the other hand is living out the ultimate 14 year old boy fantasy - sex with the hot hot teacher. So when the sh*t hits the fan, he doesn't quite know what to make of what happened, but isn't nearly as traumatized by it all as the girl in scenario 1. In this scenario, both parties are driven by lust far more than by anything else, whereas in scenario 1 the male is acting on lust to a far greater degree than the female.
I realize that I am being very general here, but that's my take on what I see as being the difference.