Maybe another easy one, maybe not. (Can include title)
I am the horror that lurks behind the glass.
I am often one shape, but I can wear many.
I am the stability between two.
What am I?
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Sign up to join this communityProbably not, but made me think of
A ring
I am the horror that lurks behind the glass.
Engagement rings! YIKES!
Edit: Oh right...
The movie "The Ring" about a demon thingy that comes out of the TV screen (which used to be made of convex glass) to attack people that watch a cursed video tape (an ancient recording device)
I am often one shape, but I can wear many.
Yep; there are some pretty kooky designs
I am the stability between two.
Wedding rings...
Purity, Power, and Promise
Promise rings, Purity rings, Rings of power
Maybe a bit too much of an imaginative solution but:
An eye?
I am the horror that lurks behind the glass.
Behind each lens on a pair of glasses is an eye
I am often one shape, but I can wear many.
Usually spherical, but there a lot of species with different shaped eyes
I am the stability between two.
Bit weak, but it transfers what you see (the first) to the brain (the second) and is in between.
How about:
a reflection?
I am the horror that lurks behind the glass.
a piece of glass can like a mirror show some reflection behind it
I am often one shape, but I can wear many.
Your own reflection is always the same but of course you can see other objects in the reflection also
I am the stability between two.
Maybe to indicate that you and your reflection are identical
Is it
Mannequin
I am the horror that lurks behind the glass.
Mannequins stand behind the display glass of the showrooms
I am often one shape, but I can wear many.
One mannequin can wear different size clothes
I am the stability between two.
Not sure about this one.