Permanency, another of my favorites, ah yes!
MASSIVE DISCLAIMER: It may have been (a little) obvious from the way I wrote it, but, these journals of fetish reviews are based on stories, games, scripted videos and such that I've seen around the web, practice of these fetishes outside of fantasies has not been directly experienced by me, so all thoughts and writing could be very much different if they were to be experienced in real life to as fantasy, roleplay, writing, etc., others may view them in different ways, this is just the way I see it! Thanks for understanding!
Permanency is in a sense closer to the dark side of fetishes, also closely related to several other fetishes (namely glue), a sense that something is done and cannot be taken back, high risk high reward in many senses.
Forced punishment, 'accidents', almost always ends up with something being one-way, (Permanent glue, indestructible metal, superlocks, etc.).
A crossdressing guy stepping on a glue trap and, someone getting permanent makeup or a one-way locking corset or set of bondage, many things can be permanent one way or another.
I imagine this is more a fetish biased towards the -very- dominant people or extremely submissive servants, the former because they can threaten with something permanent, such as a chastity belt, clothing or the such to someone else, it would be a fate as bad as being encased in stone, which also comes in the package of permanency, being stuck as a statue is in there too.
The submissive ones can have that joyous feeling of masochism fulfilled with something that is permanent or near-permanent (More often the former than the latter), like dressing up in locking clothes and some kinds of permanent glue and makeup, only to realize (or knowing beforehand) the 'permanent' part was not just a brand joke.
Overall, it's fulfills a very wide range of tastes for more 'dark' types of stories, and adds a touch of reality at times, 'Permanency is no joke'.
Verdict and final thoughts:
Permanency is a very common touched theme in 'forced feminization' stories, with guys being permanently stuck in female clothing, with glue, indestructible cloth and the such, and often in TF stories as well, as one-way transformations count as permanency right?
It doesn't always include other fetishes, and permanency is often not used alone, but rather used along other things to make it more 'satisfying', if it could be called that, one-way things are one-way, and cannot be separated.
Other related fetishes and recommendations:
Glue (Of course, permanent glue under silly names such as 'eternibond', 'permaglue', and others can sound like a joke, industrial adhesives often also fill this role in stories, and in a story I read recently, 'A glue so permanent it was removed from stores' or something, good for all kinds of permanency).
Forced feminization (Also good with the above, being stuck in a frilly skirt and bright glittery makeup is wonderful for some, and horrifying for others, for all the good reasons).
Bondage (Permanent bondage is something extremely fantasized about by many bondage players, as with real world limitations, the frail human body would eventually either need extreme care or such to remain in permanent bondage of any sort).
Transformation(TF &/or TG) (Magic, science, one-way transformations of any sort, often being permanent in various stories, and often attempted to be reversed often with negative results).
Final personal score: 8/10 (Damn dark but so good!)
I wish I could cover this more, it's a theme I think I will touch more upon if I continue writing stories, but I think it would be hard for me to cover it whole!
The fetishes recommended are very similar to the last ones because they are very similar fetishes (to me), really sorry!
If you have any suggestions on any future 'reviews', do tell!