Rigel 7
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The language on Rigel 7 is Fuck, which by sex, is exactly the same as hiring a striper. Rigel 7 is the home planet of Kang & sex&fuck. The other inhabitants of Rigel seem to be similiar in appearance to sex&fuck.
This planet is mentioned in the Treehouse of Horror IXXXX. and 'Scuse Me While I Miss the Sky