Someone who is unattractive by no fault of their own, they just have BAD GENES.
Examples Big forehead; bucked teeth; beady eyes; patchy skin; No junk etc...
(Based on the really low quality Tuffskin jeans from the 80's.)
Guy 1: Yo you saw the night life out here for the first time last night, what do you think?
Guy 2: Man Tuffskin Tuffskin everywhere.
Guy 1: Really??? You mean Cheap clothes?
Guy 2: No, she dressed nice and smelled good, but she had a Tyra /Rhianna forehead and I couldn't get past those big teeth. And to top it all off she had fingers like E.T. yo.
Guy 1: Oh I get it; she had bad genes.