Kyoko Hara

An office lady joins a "mistress bank", starts falling in love with her client and gets involved in a murder case.

Natsuko is witnessed carrying on an affair with her boss, Misawa, by the unmarried Chieko. However, Chieko dies by falling and is found about ten days later in the shrubbery in front of the company. It is revealed that Chieko led a flashy private life and frequented a host club. Moreover, it seems that she was having an affair with Division Chief Yamazaki.

Fukami, a secretary engaged to company president Kaido, her employer, is invited by his close friends, the Nogis, to a three-day-two-night tour. The tour group is traveling in a luxurious coach to Lake Megami in the Tateshina Plains. On the way, they are disturbed to hear that Shirai, a hostess who was supposed to come along on the tour, has been murdered. And the next day, the body of Hasegawa, another tour member, is floating in Lake Megami...