Oku Aizu No Ningyo Hime

[Machine Translation] Kajiuchi visits Okuaizu at the invitation of his best friend Chikage and meets Otone, a beautiful girl who is married to Chikage. Kajiuchi is completely charmed by the beautiful and good-natured Otone, but Chikage tells him a surprising story when she is not around. She tells him that Otone was actually the one who drowned in the bathtub the other day, and that she married Shiori, who was a twin of Otone. Shiori's character is twisted because of her past relationship with Chikage, but there is no way to tell apart except for a mole under her lip. She reveals to Kajiuchi the frame of the exquisite photograph "The Mermaid of Okuaizu," which was taken of her drowned, nude daughter. The stage 4 cancer-stricken Chikage is dying, and Kajiuchi accepts her life-threatening request and begins to solve the mystery of her love-hate relationship with Chikage. This is a shocking mystery novel that unravels the mystery hidden in a single photograph of his daughter's death.

親友千景の誘いで奥会津を訪れた鍛冶内は、千景の結婚相手である美少女乙音と出会う。美しい上に性格のいい乙音にすっかり魅了された鍛冶内だったが、千景は彼女がいないところで意外な話をする。それは先日湯船で溺死したのが本当は乙音で、自分が結婚したのは乙音とは双子の間柄だった汐里ではないかというのだ。汐里は千景との過去のいきさつが原因で性格がねじまがってしまっていたが、唇下のホクロ以外見分ける術がない。そして溺死した全裸の娘を撮影した絶美な写真「奥会津の人魚姫」のフレームを鍛冶内の前で露わにする。ステージ4のガンに冒され、死期が近い千景の命を掛けた頼みを受けた、鍛冶内による愛憎を巡る謎解きが始まった。娘の死を写した一枚の写真に隠された謎に迫る衝撃のミステリー小説。