When you are banging your partner while he/she is in reverse cowgirl position (cowboy hat optional), you observe that his/her anus is a little feces-stained. Thus, being the generous fucker that you are, you grab a tissue and wipe your partner clean.
After a long day at lab, I was looking to pin Sarah down and do her from behind. Maybe try out the old nasty western blot.
by John Mustache June 12, 2008
Get the western blotmug.