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Snowballing

With contributions by cum swapping. - Thanks!

Give a man fellatio. Let him come in your mouth.  Hold the semen in your mouth until you can give it back to him a French Kiss.  You will have snowballed...

Dan Savage Says
"Some of my very young, very old, or very sheltered readers (hello there, Mom) are no doubt asking themselves, "What is this snowballing shit?" Well, simply kissing someone who's just finished giving you head isn't snowballing. That's just gratitude, appropriately expressed. When a couple snowballs, the person giving head (PG) doesn't swallow after the person receiving head (PR) comes. Instead, the PG retains the semen in his or her mouth, and then kisses the PR. As they kiss, the PG passes the wad of semen into the PR's mouth. Yes, I know: YUCK. But it's not over. The PR, mouth filled with his or her own come, passes the come back into the mouth of the PG, who passes it back into the mouth of the PR, who passes it back into the mouth of the PG--and back and forth the wad of semen goes, mixing with more and more saliva, the wad getting bigger and bigger with each pass (snowballing, get it?) until either the PG or the PR decides to swallow or spit, or one or the other or both of them drowns. Yes, Mother: YUCK. "  Source: http://www.thestranger.com/seattle/SavageLove?oid=14052

Clerks
For many people, the word Snowball entered their vocabulary from the 1994 movie Clerks, by Kevin Smith- who rocks 18 kinds of toast.  A character in the movie has the nickname snowball, because he really enjoys it.