flat pussy
A flat pussy is one that has been pounded so many times that it could now be conceived as flat. This implies multiple poundings, however, a pussy could be made flat by one very intense pounding.
Man, that cat was run over so many times, that's a flat pussy.
Man, that girl was fucked so hard, that's a flat pussy.
Man, that girl was fucked so hard, that's a flat pussy.
Flat Pussy
A pussy without any discernible lips whatsoever.
That chick has got flat boobs, flat ass, I bet she has flat pussy too.