"You wouldn't rat on me to Rachel and Carl, would you?"
That's more like it! That's just the sort of attitude you like to see.
She wipes the jave-spittle off her mouth with her sleeve. Brett comes over and refills her cup, eyeing Maggie's bosom enviously before slinking back to the bar with a resigned sigh.
Maggie is now staring at you with suspicion.
"Hmmph. Why should I believe you know anything incriminating about me at all?"
Sounds like Maggie needs some convincing. Why don't you threaten to reveal:
(1) Her treatment of the servants
(2) Her masquerading as what's-her-name
(3) Her artistic ability which she often thinks of turning into a profession