Housekishou Richard-shi no Nazo Kantei 7.16
Other Name: The Case Files of Jeweler Richard, 宝石商リチャード氏の謎鑑定
Summary: The novel follows Richard Ranashinha Dvorpian, a handsome British jewelry appraiser, and Seigi Nakata, a bright and upright Japanese college student. The duo solves various jewel-related cases by unraveling the hidden psychological aspects of their owners that lie within the gems.