Top definition
A sexual move involving you secretly blowing your bonersauce on a partners back and then having them slip their shirt back on. The sloppy jizz blizzard still on their back results in a soggy backpack.
That freak I railed last night threw her shirt on too fast and walked out with a soggy backpack.
by CrustyRubbers July 20, 2011
Get the mug
Get a Soggy Backpack mug for your fish Helena.