The People of Ravenend House.

The noble mansion Ravenend House stands in the countryside, home to an eccentric master and his loyal staff. One quiet day, the butler, Mr. Condor, suddenly disappears. A trusted figure who had always been relied upon by the servants vanishes without a trace… Where could he have gone? The peculiar master, Lord Ravenend, stays locked away in his room, offering no help. Then, one day, a young butler arrives to take Condor’s place…? As this new butler enters the household, the quiet routine of their daily lives begins to unravel…

(Source: Kadokawa, translated)