Nakata Seigi, a college student with a strong sense of justice, saves a jewel dealer named Richard from some trouble with a few drunkards. Nakata receives an appraisal of his grandmother's ring, which she protected until her death, from Richard. Through this, Seigi learns of his grandmother's thoughts, feelings, and the truth of her past. Afterwards, Seigi begins working part-time at Richard's jewel store, "Jewlery Etranger". There, Richard and Nakata's friendship begins to change as they solve the mysteries they encounter and hold onto secrets that no one else can know.