Varla decides this sub needs some training - breath training AND CBT training! She thinks his balls are too sensitive and need some conditioning. She teases him with her ass. Then she grabs him by the balls and squeezes them, while she muffles his cries by smothering his face in her ass. She does this over and over again - teasing and smothering him -- leaving him dizzy and lusting after her. She knows that squeezing his nuts makes it even more difficult for him to hold his breath. He has learned by now that such rewards from Miss Varla always come with a price.