Super Munchkin invokes this trope with an enemy named "Misunderstood Man." He's depicted as a bespectacled supervillain in slacker clothes surrounded by fawning heroines, and female characters cannot fight him.
Tieflings in Dungeons & Dragons. They were originally just humanoids with a trace of demonic blood in their heritage who tended towards evil and were available in supplemental material as a playable option for P Cs (though they were meant to be monsters), but by the time 4th edition came out, they were their own true breeding offshoot of humanity with a full fleshed out backstory and they were available in the core player material as a default player race option alongside elves and dwarves.
