To take another man's turd and shove it up your own ass and then to shit it back out. This can go on for a "Double Fandangler" maybe even a "Triple Fandangler." Where you repeat the same process several times.
I don't buy the schmegegge about Morty sleeping with Moira.
His version of the story was pure schmegegge.
The whole schmegegge was made up to get Liz a little bit of attention.