This is a term used to refer to people who push themselves into your house as soon as you let them put their put in the door. Metaphorically speaking. If you give someone an edge of hope or anything, they will try to take advantage of that and get more.
Sally: Ugh...so my prom date wants to take me out on a date. Like more than friends.

Brenda: Well, if you give a mouse a cookie...
by Wise Gal February 11, 2012
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