A sex act, similar to the rusty scupper, where a man and woman are engaging in anal sex because she is having her period. Shortly before climax, she pulls out a strap-on and rubs it all over his face. She then yells "Welcome to the Thunderdome Bitch".
Much to his eventual dismay, Lisa pulled a rusty brain on her boyfriend while she was having her period.
by Brucestafer August 3, 2008
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