The instrument was cold, a clinical intrusion, but the familiar hum of the vibrator promised a counterpoint of heat. Elara worked with practiced precision, her fingers guiding the slender, flexible shaft of the endoscope through the intricate geography of her own body. On the screen beside her, the pink, rugose walls of her vagina glistened under the LED light. She watched, detached and fascinated, as the tip navigated the folds, seeking the ultimate landmark.

There it was: the external os, the tiny, dense pucker of her cervix, a dusky rosette of tissue that was the gateway to her womb. It was normally a firm, unyielding sentinel. She applied the rounded, buzzing head of the vibrator directly to her clitoris, and on the screen, she saw the subtle, immediate response—a slight flush of blood, a minute relaxation of the complex musculature. The orgasm that followed was deep and spreading, a warm tide that originated not from her clitoris but from the very core of her, a resonant, full-bodied shudder that made the cervical os on the screen flutter and soften almost imperceptibly.

It was this response, this fleeting window of physiological vulnerability, that became her obsession. Each subsequent session was a deliberate experiment. A clitoral orgasm to prime the system, then the swift, calculated application of the vibrator’s tip directly to the os itself during the peak of sensation. The vibrations were a low, pervasive thrum transmitted through the dense tissue. She watched, breath held, as the tiny central opening, no wider than a pinprick, would visibly yield, dilating by a fraction of a millimeter for a few seconds before contracting back to its resting state.