Getting locked in some kind of fetish garment, or more general, just not being able to take something off. That could be done with actual locks, or glueing something closed, or just actually getting sealed in something, that when dried / finished processed, has no opening. The tag Chastity is always combined with this of course.
Oops! by Mikel
Oops! by Mikel (Archive Link) Another story by Mikel about the main character locking themselves into something. Darla starts by locking herself in her corset for a day while going to the office and this only continues in the evening, as she gets a bit of adventures with her ballet boots and chastity belt. She just slips up a bit and is not locked in her boots and corset for quite some time. ...