Boobs on girls that are caused by them being fat, not by being girls. It has nothing to do with hitting puberty, but with being a fat lard. Usually the said girls like to wear shirts that hang down so you see their fat crack in between their boobs, which no guy likes at all. Some of these girls are really slutty and think everyone wants them.
Ew, dude, did you see that girl over there with her pig cleavage? She's wearing a shirt that should be illegal for her to wear.