A condition in women that is analogous to the condition known in men as blue balls.
Such situation arises when a female is sufficiently aroused through foreplay with a man/women to the point at which her vagina becomes lubricated anticipating sexual penetration only for the man/women abruptly refusing to penetrate the aforementioned wet vagina.

Such an unexpected and non-erotic climax renders the lubrication of the vagina unnecessary and as a result it drys very rapidly forming a crust on the labia of the vagina.
1. Q: "Bro, did you put away that girl the other night? She was gagging for it"
A: "Na Bro, she wanted it but I said no and she got Crust Labs..... I still got a wristy though"
Q: "Niiiice"

2. Q: "Bro, did you bang that slut the other night?"
A: "Na Bro, I decided to Crust Lab her, that way she'll want it way more next time"
Q: "No doubt baby"
by deepseatrawling March 3, 2014
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