In this context, I think that any or all of those things are possible, feasible. I'm perfectly OK with spooky story telling, it just doesn't seem like a very reasonable worry within the context. I'm not saying that the context itself is entirely reasonable, I'm just saying that it seems like unnecessary fearfulness or paranoia. In this case as you can see by responses to this thread, this kind of spooky speculation is not being experienced at all as fun, but as a meaningful barrier to real world experience, which is why I interrogate it a little bit. Not to close off meanings necessarily, but just to interrogate them.
As you suggest, with my examples especially what I was trying to question was the idea that human ideas of evil apply to this context. What is an evil spirit, a sociopath who is so chronically lonely for human company that it kills people? A fame-hungry narcissist? Whatever! - these are totally human ideas of "evil". I maybe think "evil" altogether is a fairly ridiculous concept, because it tends to operate in some sort of mythologising way to turn something that is actually quite mundane into something that is overwhelming and absolute. I understand that others don't always think that way, but I think they should at least consider it.
So you want to talk to Aunt Dorothy in the bathroom mirror and see if she says anything back. Oh no, an "evil spirit" might answer instead! Well so what if it does? We are grown ups and can handle scary things. Look away from the mirror if you get frightened and go talk to the plants instead.
Regardless as you say if it's an aspect of ourselves given a new form - we could learn something.