Fifth delivery in the Tarao Bannai series, following the "master detective with seven faces" who uses his signature disguise to solve crimes with a double-barreled pistol.

Keiko is pretty and intelligent but her home life is not a happy one. Never having known a father's love, she develops a possessive attachment to Mr. Mazaki, the new mathematics teacher.

The story of Kiyoko, a young woman who has successfully managed to make a break with her dysfunctional family who have been trying to arrange a marriage for her with a disagreeable man whom she has rejected.