A situation in which two individuals, who were once in a relationship but are no longer together, continue to have sex with each other on a regular basis and still act as if they are in a relationship. Alcohol and or drugs enhances this effect to unknown levels.
Observer 1: What's up with Jim and Amanda? I thought they broke up?

Observer 2: They did, but they're caught in the J&J Effect.

Observer 1: Oh, I see. It's a sad sight to see.

Observer 2: Indeed
by Razilla Killa April 13, 2010
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