Part 4 was a lot of fun to read, and left me with some interesting thoughts to consider as well
It is good to learn a bit more about our central man, and his history, slowly fleshing out the character as a person, to learn something about what he wants from all of this, and what is driving him. Also we are slowly learning more about the other people here as well. Good to see some well rounded characters growing as we learn more about them, and see more of them and their world.
One interesting take away is that he is clearly relatively well off, which makes it even clearer why and how he is happy to accept the rather small running costs of this "prison" and the staff, in order to live the fantasy, to indulge his desires and see where this gets him. After all, how come he is willing to spend so much on all of this, and what is he getting out of it, is a central question to all of this.
Taking Paula along for the checkin, and confirming that both Paula and Heather knew and understood what this meant, was interesting. We are clearly reaching the point where Paula really is on his side, and is accepting, and getting happy, that keeping and treating Heather as a prisoner, as someone less than the others, is acceptable and appropriate. Looks like Paula is shifting from fighting all of this to supporting, encouraging and helping this along.
Seeing the blowjob and then Paula spitting it out onto Heathers face was a real eye opening moment, since it marks such a clear and obvious change in her treatment, and acceptance, of what Heather really wants and needs while being a prisoner. And that is after the muscle pinching pain, but there is a difference between pain and that sort of sexual humiliation and taunting!
Ordering her not to communicate at all, and with the possible punishment of weeks or even months of denial! That seems almost to harsh a threat, especially for such an odd order, so I am with Paula in wondering what the point of all of that was, but the explanation, but even more, watching the others interact with their silent and refusing to recognise them prisoner really brought home the effectiveness of this order, and the point it was making to everyone.
Watching how they got increasingly frustrated with her, and the men especially were treating her much more like a sexy object than an equal, really showed the effectiveness of this rather strange yet simple order. A clever idea, and it is working well!
Even her friend Maggie seems to be coming around, but obviously that is going to take longer to really happen.
Then we have the shop in the village, so many fun BDSM toys available and in stock, but much more than that, leather and metal workers are available?! Is this just general world building, or is this a hint that such skills will be useful in the future, to move things forward a bit?
Finally I am left wondering how you have worked out where to take and end this, since we have now been told clearly that Heather wants and desires a 24/7 experience, and this is something that most people simply aren't interested in, understand, let alone able to provide. So is he going to just let her go at the end? Or is some other solution possible down the line? Time will tell, and it will be interesting to see
