Porn lingo. Fitting.
No. Pool/Billiards lingo. Of course, you may have picked it up elsewhere...
Some players use repetitive playing of solo three-ball as a form of practice, especially using the 8 ball and 9 ball (because they are the "money" balls in their namesake games and thus the most likely to be "choked" on), along with the 6 ball (or whatever ball is closest to the color of the cloth, if not playing on a green table) since it is the hardest to see clearly. This form of practice is used as a drill to hone position play in "closing the deal" (the all-important last three shots common to both major games - run-out setup, money-shot setup and money shot). A nine-ball-inspired variant is to use the 9 and two other 1-8 balls and shoot them in ascending order, like the end of a real nine-ball game.[2] An eight-ball practice variant is to use two solids or two stripes and the 8 ball, and shoot the 8 ball last. Other practice variants can adapt rules from one-pocket, bank pool, the bank-the-8 variant of eight-ball, and other games.
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LOL, sorry - no sale. UFU cultists and the porn industry run together, everyone knows that.