No @selinaminx there is no bag involved here, but you got the dehumanization right :)
It’s a tight leather garment referred to as a “bitchsuit” that removes the usability of arms, hands, legs and feet, forces a movement scheme much like a four legged animal, and with hood that is an integral part and that obviously removes any possibility to see.
The bitchsuit in this embodiment is designed to isolate and dehumanize the wearer. There is no way to get out of it without help from the outside, and with a locked collar the zipper won’t be easy to work. The identity is hidden by the suit, all the wearer becomes is an anonymous pet. And like you would leash a pet the chain padlocked to the collar aims to keep the wearer secured in place.
If the suit is combined with a gag and some earplugs underneath (as @fawnstarflare likes to do to it) the world as you know it stops to exists the moment the suit is zipped up and closed. It all becomes a dark quiet place, and as the body heat slowly warms up the suit it will feel like a second skin. And that is a very intense experience of dehumanization at its best.
The suit also have the feature (if it has a crotch zipper, and it should for hygienic purposes) that the sex is easily reachable from the outside, and there is nothing the wearer really can do about it, not pleasure itself, nor stop anyone else to reach there. If you thought it was intense just to be sealed and locked into a suit like this, think about the feeling when you realise exactly how helpless you are.
And that, is why it loves it!