Yes, Rekka would be able to use ofuda to seal ayakashi's evil energy into a small area -- in the case of something like a room, it might be able to leave via an unsealed entrance if she blocked the door (for instance crawling out a vent or breaking the window.) In the case of something like a jar, sealing the jar mouth would effectively keep an ayakashi inside for as long as the seal lasted.
In regards to teaching other people how to do things like this with ofuda, they would have to have some sort of canon "magical ability" that's compatible with spells from Rekka's world, and they should take a reasonable amount of IC time to learn the process (comparable to what it would take people to learn this ability in Rekka's home canon.)
no subject
Yes, Rekka would be able to use ofuda to seal ayakashi's evil energy into a small area -- in the case of something like a room, it might be able to leave via an unsealed entrance if she blocked the door (for instance crawling out a vent or breaking the window.) In the case of something like a jar, sealing the jar mouth would effectively keep an ayakashi inside for as long as the seal lasted.
In regards to teaching other people how to do things like this with ofuda, they would have to have some sort of canon "magical ability" that's compatible with spells from Rekka's world, and they should take a reasonable amount of IC time to learn the process (comparable to what it would take people to learn this ability in Rekka's home canon.)