Heart rate monitor (Pixiv Fanbox)

Seemingly getting closer and closer, with each turn of the wheel and each feather gently stroking from top to bottom across your crotch while almost being able to feel each hair brush against your most delicate parts – but with no relief in sight. What a wonderful nightmare~ This trainee finds herself at the hands of a machine, that doesn’t give in to watery puppy eyes or screams of frustration. All it does is measure the trainee’s heart rate. If it increases, the wheel slows down. If it decreases, the wheel spins up. Never enough to let her reach an orgasm and never enough to allow her to rest. The only thing she can do is wiggle in frustration while she’s drenching herself in her juices~