Implied is this girl is not like other girls because she goes occasionally defies toxic patriarchal conditioning to be a passive object. Instead she flips the script and actively pursues, objectifies, is assertive, brash, cheeky, aggressive even. Generally not demure, and therefore special.

People sharing may want to identify with the girl who is but slapping due to an unarticulated desire to rebel against oppressive gender roles themselves, while still being CIS, (but not in a terfy way, just in a look, there is no patriarchy! Other girls are naturally so repressed they are basically not even people, but not ME, look, i'm cooler than other girls kinda way)

That's my very noob read on it anyway.

But slapping without consent is assault. Without context we can't really say that's what this drawing is supposed to represent.