Kanji Title: 宝石商リチャード氏の謎鑑定
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On a seemingly ordinary night, university student Nakata Seigi rescues a beautiful Englishman named Richard from a group of drunkards. Richard is a jeweler who travels around the world to sell jewels to clients. Together, the two begin to solve mysteries surrounding the jewels they come across and their owners, starting with the mysterious pink sapphire ring that Seigi’s grandmother left to him.