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The act, or more aptly; The rather unfortunate act of reaching climax at the exact moment a plane comes crashing through your roof. For this act to be properly performed, your family* must be in the next room when the plane reduces your masturbating ass to charred dust.

*Your family obviously excludes your sister. Who should be at my house working on taming her gag reflex.
"Did you hear about that guy who had a Planegasm? His sister gives GREAT head now!"

"So your whole family was across the room when she came? I'm so sorry to hear that..."
by Epa Epar August 24, 2011
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