Most guys, and even many women, do not know this. The clitoris becomes engorged with blood upon arousal, making it hard, much like a penis. The term derives from the shape of the clitoral glans (the round part under the clitoral hood and the part that can actually be seen) and how hard it gets.
I got my girlfriend so horny that she got a glass marble.
by annarky June 7, 2014
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