Captured by Charybdis

'Now, Miss Kraken, that was very impudent of you in there. Or was it? Did you enjoy your punishment? Was that what possessed you to be so disobedient?' the 'doctor' accused, turning around and lacing his fingers, making sure the gloves were fully on. His voice was muffled slightly, but against the absolute silence she could hear all. The sound of three respirators operating slowly was the only answer, each of their breaths dragging through the layers of protection, purified by their passage.
'Just a few routine checks and we'll move onto something more interesting, Miss Kraken,' he stated with mirth, mocking her plight as one of the women stroked her hair, seeking to calm her. 'Now if you'll just relax...'

Mina, an agent of industrial espionage, is hired to investigate the secretive hidden project of a powerful industrialist. Following the trail to Project Charybdis, she finds an underwater world where female slaves serve the lusts of others, unable to escape as they are transformed into latex-bound mermaids, pets, and objects of carnal excess. Some are paid to be present, others are captives who have been abducted and forcibly trained to serve.

Having blundered into the project, Mina joins the rubber-encased ranks of the deep-sea harem. There she finds new pleasure in her strict captivity as she surrenders herself to those she had been sent to expose, and who now subject her to endless and ingenious acts of depravity.