People knocking at his door was not necessarily an uncommon thing. Though usually if it was someone he know, they tended to walk right in. The knock Peter heard when he was inches away from relaxing in his comfy chair with tea and his latest Latin text on angels, was incredibly polite, and Peter was convinced it was either Spectre or Johan. Only they knocked like that. Most of the people he knew sounded like elephants stampeding when they knocked.
( Not stampeding elephants )
( Not stampeding elephants )