edgeplay
In BDSM, edgeplay is activity that either crosses the line or borders on doing so. Examples are erotic asphyxiation, fire play, knife play, fear play, wax play, erotic electrostimulation, erotic humiliation, and most forms of genital torture.
Acts that cross the line imply gore, mutilation, or even death.
Not to be confused with edging, an act of either orgasm denial or a self-imposed challenge.