Describes a mate or partner that has perfected his craft through years of seeming like a great catch when in all actuality...he suddenly, and stealthily reveals himself as a complete douche bag.
Great husband and family man...and poof, the douche ninja comes out of nowhere and reveals that he is a cheating, lying scumbag. You had no idea. Surprise attack. Many victims.
by Sonny James August 29, 2013
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