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Johnny says very little, which spares him from accusations of being a "squealer", but his reticence tends to be unhelpful to himself or others. Johnny's catch phrase is "I ain't sayin' nothin'!". Johnny is in his 30s. His occupation is a Mafia associate. Johnny has short black hair. Johnny wears a purple suit.
When there is a shoot-out in Fat Tony's mansion, and Johnny is shot by accident. When asked where he is injured, he says, " I ain't sayin' nothin'!", and when asked what to tell the doctor, he says, "Tell 'em to suck a lemon."
 Behind the Laughter
Johnny Tightlips is a reference to Frank "Tight Lips" Gusenberg, who was shot down in the real-life St. Valentine's Day Massacre in Chicago and replied "nobody shot me" while dying.
On the "Insane Clown Poppy" commentary, it is discussed that the original name for the character would be "Tightlips Johnny"