Everyone else left at six.
Seren knew this because he tracked it — not deliberately, not suspiciously, just in the way that someone who was alone in a building with a person they were trying not to think about tracked the presence or absence of other people as a matter of structural awareness.
Six-twelve: the last assistant.
Six-eighteen: the overnight security rotation beginning on the lower floors.
Six-twenty-three: Damien, who never left before six-twenty on any day Seren had observed.
Then it was just them.
The floor. The evening light from the windows. The particular quality of silence that forty-three floors above a city produced when the workday was officially over.
Seren kept working.
He had not been asked to stay.
Caelan had come out of his office at five-fifty with a document and said, without preamble: "The acquisition brief from Tuesday. There are sections I want to revisit."
"Now?"
"Unless you have somewhere to be."
He didn't.
