a) It’s a sneaky derogatory name for a “mean girl/queen bee”.

She may think it’s a complement referring to an expensive Starbucks cappuccino, but it really means she’s pretty and popular on the outside, but she’s a rabid bitch on the inside.

b) It's a term used to describe a girl who may look cute and sweet, but she’s really a rabid bitch from hell.
Example a:

Mean Girl: I was just kidding about you being a beast.
Victim: Aww, you really are frothy and delicious.
Mean Girl: Thank you!

Example b:

Guy 1: How does a girl turn into Bridezillas?
Guy 2: She starts out cool, but watch out, deep down she's frothy and delicious.
by cricketkicker June 19, 2010
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