Katie sat alone in a compartment near the end of the train. The corridor outside was quiet for once—most of the older students had already staked their claims, and the first-years were being herded about by a frazzled-looking prefect.

On the seat beside her, tucked between her bag and her robes, was something she hadn't put there.

A ring.

Silver. Simple. Unassuming.

And humming—a faint, steady thrum she felt more than heard, like a second heartbeat pressing against her ribs.

There was no note. No name. Just the ring, lying in plain sight, waiting.