Protagonist somehow ends up in a situation where she has her wrists tied behind her Back, with rope or handcuffs, and she is topless. She IS also weating a vibrator, under panties or otherwise. Vibrations gradually increases and intensify. First slow, shorter periods with longer pauses. Then gradually stronger, longer, shorter pauses. Varying programs with vibrator. She has to find a way to get free. Not easy. Often needs help from men. Embarrassing. The vibrator IS locked. Kind of like a chastity belt. No key. The programs must run to The end to unlock IT.