Without her, he was nothing. She had created him, and in a sense that made her his mother -- but in the way a puppeteer is the mother of a puppet. That was all he was, really. Just a puppet, a toy in the hands of a greater power. He was simply one tiny piece of a very complex trap, all designed specially for Coraline. But he was the only one, the only toy, the only piece that did not do what he should have, and she had known it from the start. That was the real reason why he couldn't talk.
A part of him was happy that Coraline had defied, had sensed the metal jaws closing around her and resisted the bait. But most of him was sad that it had to end this way. He couldn't even tell her goodbye, much less anything else. But he'd wanted it like this. It was the best way, the only way -- well, the only way besides...
And Coraline wanted him to come with her. He couldn't explain now that he could only exist in this world. Even if he could speak, there was no time. She was coming.
He was going to take the punishment. Not Coraline. Him. Coraline was going back to her real world, back to her real life, back to the chances that he'd never have.
He closed the door, and Coraline was gone.
By the time it opened again, so was he.