Original Sin 3

Original Sin 3 by AnonymousPseudonym

If you're wearing any clothes, take them off - but continue stroking while you do so. I hope this doesn't present a problem.

Once you're done, or if you're already naked, start stroking at a medium pace. Use your free hand to smack your balls 5 times as far apart as you want, as long as you're done before you complete 50 strokes.