Mistress Quickly is a member of Falstaff's gang.
She was eventually taken prisoner by the Squad.
Mistress Quickly possesses extraordinary speed.
Mistress Quickly is named after Mistress Nell Quickly, the landlady of the Boar's Head Tavern in Shakespeare's Henry IV plays. She is fond of Falstaff, though at times exasperated with his unpaid tavern bills and constant borrowing from her. (At one point in Henry IV Part Two, she even calls in the police to demand that Falstaff pay up, but they prove no match for the fat old knight - and neither does Mistress Quickly, after he flatters her into lending him more money.)
In Henry V, Mistress Quickly, now married to Pistol, reports Falstaff's off-stage death in one of the best-known scenes of the play, describing him as having gone, not to Hell, but to "Arthur's bosom" (generally considered a slip of the tongue for "Abraham's bosom").
Mistress Quickly also appears in The Merry Wives of Windsor, but as a maidservant to Dr. Caius, rather than as a tavern-keeper, and seems to be an entirely different person with the same name. (This is one of the many discontinuities between The Merry Wives of Windsor and the Henry IV plays.)