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1.
To preform a Diocletian is the high water mark of a EPIC sexual life. The move requires four separate girls (one from Turkey, one from Serbia, one from Italy and one from Germany) and three other bros. First you make it appear like you are going to have all 4 girls to yourself. Then you invite the other bros in, each to take one. All present climaxing at the same moment.

The ultimate expression of power and bro.
That must have been one crazy party, i heard Chet got a Diocletian to work
by Classical Biographer Plutarch December 28, 2010