...The doors unlocked and Albedo was gone.
Though, to be fair, we'll back up a moment to add context.
The shift was not a gradual thing--Albedo's day had been interesting, to say the least, but it was not altogether bad. The adjust came right before the boy took off, when the link flared between black and white with little context. And Nigredo only felt confusion, then a sharp fear that burned, then the strong pulse of heavy anger. There was no context, as stated, and Albedo had a ring that went to his brother's door. The reaction, then, was understood; the action only the simplest of what would be done.
Albedo sent a demand and a concern at his sibling in advance, then, in some fury, slammed his hand against the wall.
[teleporting to
here]