The predilection for masturbating into a full hot water bottle. At the crucial moment of ejaculation, an involuntary spasm overcomes our protagonist, leading to a back-ejaculation (or ebaculation, if you will) of the hot-water bottle's contents onto that most sensitive of areas.

The result: walking like John Wayne.
"Don't worry," the orthopaedic surgeon said to Peter's mother, kindly. "There's nothing wrong with his legs. It's just a particularly vigorous case of adolescent John Waynism."
by GrrB August 24, 2009
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