Red colored bedding which serve the function to disguise any period leakage during intercourse and wash out easily later at the laundromat. Commonly found in the closet of a morally lenient female, or already on her bed depending on her level of leniency. Shameless men will regulary make their bed up in period sheets as they will sleep with anything any time.
Pat "Dude, I went home with this girl last night who got her period all over her white sheets so she made me buy her period sheets this morning so she's prepared next time."
Darron "Is that all?"
Pat "Hell no, I bought her Plan B too."