Preparing to make fun of somebody, hence the term "crumb," which means to make fun of. The term parodies medieval battles with archers getting ready to fire at their enemy.
A completely unattractive chick walks by and two guys are trying not to laugh.
-"Oh God..."
-"Get your crumbs at the ready!"
And away they go teasing her deliberately.
by acrestare July 1, 2011
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