Back For More (Infected Voices #6) by Robert Essig
The lights are bright to show everything in vivid detail. There are whips and chains and floggers and thumb cuffs and spikes and nail-studded paddles, and . . . oh shit . . . The isolation. The pain. The torture. The blood. The agony!
Most people are thankful to be alive after such an ordeal.
Some people come back for more.