Much like incest (except without being blood related), the act of having sex with many people within a group of friends. When friends have sex with each other and pass each other on to their other friends for more sexual activities. Scenecest is very common among "scene" kids.
Johnny has committed scenecest with 30 girls whom his friends have also had sex with. Those stains on those blue skinny jeans aren't bleach.
by Mellor Strummer March 15, 2009