Said when a confluence of thought and/or action occurs during a conversation between two or more individuals. See: Poke, you owe me a coke, or the concept of a jinx, but without the imposed silence inherent in existing concepts.
This pejorative should be shouted and/or typed at any moment when both parties involved in a conversation type or say what is essentially the same concept (with allowances for differences in wording).
The declaration should especially come into play when this confluence occurs at several moments in the same conversation; the first instance might be unique, but three or more would justify loudly shouting "BATFUCK AND MUSTARD" from any available rooftops.
A: I consider the cantaloupe to be an unnecessary fruit.
(simultaneously)
B: I no longer require cantaloupes in my repertoire of melons.
A tropical fruit with the word fuck inserted in the middle. Used as an abrupt exclamation or utterance of exasperation, or an adjective describing dumbfolk. Also can be an expression of surprise or shock,