What is Back Jackin'?
1.
(băk'jăkin') v.- An approved method of masturbation in the workplace in which you use the upper posterior side of a willing co-worker to rub your genitals on in a slow, sensual motion. Grunting noises are an optional way of showing approval in your back jackee, but can make for awkward moments.
Chris, noticing Curt's lusting gaze at his boner, decided a back jackin' was imminent.
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