A rainbow party is an alleged form of group sex involving teenagers. Teenage girls each wear a distinct color of lipstick, and the boys attempt to collect as many different colors as they can on their genitalia by the end of the night. It may, however, be entirely fictional.
Rainbow parties were first brought to public attention by a guest on Oprah Winfrey's television show in 2003 and then continued to receive media coverage culminating in the publication of a fictional novel titled "Rainbow Party" in 2005. Media outlets covering the story rarely presented actual teenagers who claimed to participate in such events, however, and the entire concept may have been a fabrication.