In a dimly lit dungeon, Slave P kneels, eyes downcast, awaiting his Mistress. Miss M, clad in black latex, approaches, her heels clicking on the stone floor. She runs her fingers through his hair, then grips his chin, tilting his head up to meet her gaze. "Today, we explore new depths of submission," she purrs, producing a urethral sound from her bag. She lubes it, and with expert precision, inserts it into Slave P's urethra. He gasps, his body tensing as Miss M manipulates the sound, exploring his most intimate depths.