A memorial towel is the towel or other clothing item that is used to wipe away ejaculates and bodily fluids from one another after sexual intercourse. A memorial towel can be used repeatedly, to the point of disgusting crustyness, but this neglectful and lazy habit is frowned upon by the lady having semen wiped off of her vagina and buttcheeks.
a memorial towel is not always a towel. sometimes, it becomes necessary to sacrafice a sock to avoid getting bodily fluids on your other more visible clothing. sometimes, theres nothing else around but an old T shirt that gets continually and conveniently thrown behind the bed. sometimes, youre barefoot and wearing comfortable cotton pants so you decide it will be ok to use your underwear and just freeball for the duration of your downtime.
man, I had to use my awesome unicorn T shirt as a memorial towel last night