When performing a sexual act involving defecation, said defecator experiences extreme diarrhea resulting in an explosive surprise for the fecal recipient.
Bruce: Hey Lance, wanna try a glass bottom boat?!
Lance: No brah, last time we did that you gave me a Hiroshima surprise...
Lance: No brah, last time we did that you gave me a Hiroshima surprise...
by ryo101 July 27, 2009
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