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A bag (shopping bag, trash bag etc) that a male uses to ejaculate in while masterbating to maintain unsoiled bed sheets and to conceal evidence of pleasure from parents.
After my dad discovered and disposed of my sperm bag hiding under my bed, he thought it was a good opportunity to talk to me about my hormones, how to properly use a condom and the benefits of practicing safe sex.
by ericjr85 January 10, 2012