Raven of the Inner Palace Novel Volume 4 was written by Kouko Shirakawa with illustrations by Ayuko.

A number of things are disappearing around the imperial estate—several prized silkworm cocoons are missing from the Hakkaku Palace, and Kajo gets pulled into a search for another mysteriously lost object. As these happenings occur, Jusetsu and Koshun continue their investigation into what truly happened in the past. Might a nameless ghost hold the key, or does the truth lie elsewhere?