A sperm bag is a slut and whore and harlot and strumpet and slattern who thinks nothing of swallowing large amounts of sperm or receiving such amounts of sperm via being fucked either in the arse or pussy!. This could be a male or female so let's not be prejudice here.
by gaz999 September 13, 2016
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
by Jon April 14, 2004
by Jaybee_87 September 20, 2020