I heavily dislike Expies.

People who use characters from other universes. Like say, someone putting in Jeff the Killer or Naruto or whatever, even though it doesn't fit the setting at all.

I remember RPing in this one RP, forgot what it was called but it was a bank of favours. You go there, ask for something to be done and later on, you have to pay off your debt and do something also. Someone made Jeff the Killer and got accepted.

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