1 definition by MattSiscoisSexyii

Top Definition
An out of this world orgasm by an extremely sexy God-like man with a large penis that is also God-like in bed. This type of orgasm could lead to death of the woman if wild sex is performed. Usually, most siscasms happen with guys named Matt, eternal sex Gods.
Girl 1: Omg! How was sex with Matt!? Did he have an orgasm

Girl 2: Better. He had a siscasm...it was amazing
by MattSiscoisSexyii September 01, 2010
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