#spoilsport__killjoy__wet_blanket__party_pooper__partypooper  (informal) someone who spoils the pleasure of others
  supertype:  unwelcome_person__unwelcomeperson__persona_non_grata  a person who for some reason is not wanted or welcome
  subtype:  worrier__fuss-budget__fusspot__worrywart  thinks about unfortunate things that might happen

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