A rather incredible custom, if you fall in this niche. Filmed to look like a gym tutorial, you are meant to watch this AT the treadmill in a public gym. Works as a chastity tease with or without a device, since you can't get off at the gym. With your headphones on, only you, my C4S slut, hear the total, humiliating insidious mindfuck this 'tutorial' actually is.