M
M Clark A fun and frustrating device.
First off, the padlock clacking against the tube is louder than any other device so in public, strangers actually look round to see where the noise is coming from!
The shape and size means a flaccid cock is isolated, but brushes against the sides. As it becomes more excited there is no friction to allow masturbation then, as the tip starts to protrude and mistress stats to touch, tickle or spank it, the head treats like a shy mouse.
Finally the head can protrude fully allowing mistress to use all her devious tricks.
Mistress is enjoying trying to make me cum, but as yet only a dribble of pre-cum has been produced and my frustration is growing exponentially.