When someone is getting their testicles sucked on, but the person sucks too hard and it starts to hurt.
Ex. 1; "It was the best head ever til she gave me a rusty apple. I nearly cried"

Ex. 2;"You better suck my nuts good this time, last time was a rusty apple. If that happens again I'll slap the shit out of you"
by Cheeeesus Christ May 20, 2012
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