A hammering thunder sperm is:

1) A group of men or women sperming at the same time and screaming at the top of there lungs
Danielle: Ok guys im ready for the hammering thunder sperm HIT ME

Group of men: OH YEAH, IN THE EYE, ITS EVERYWHERE. shit i killed my dog, Get the mop
by Sperm Hammer August 15, 2011
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