An MSN stain is due to a raunchy MSN conversation that ends up with the guy beating off in such a hurry that he only unzips his pants and immediately starts wanking. MSN stains are usually found on the pant leg and surrounding the zipper. Stains can also be found on t-shirts if the said person was unable to hold his bunched-up shirt under his chin long enough.
Violet caused Robert to leave an MSN stain on his pants, as she repeatedly stated how she wanted his hard dick inside of her wet vagina.
by ShVR February 17, 2006