Sylvia Grab

Karin Oriyama, 16 years old. She is in high school and... she's about to get married!

Detective Suguro is enjoying a stay at a luxurious hotel in Wakayama. Also staying at the hotel is an unusual family led by rich widow Mrs. Hondo. She acts like a tyrant around her children, who are afraid of her and are at her beck and call. Unfortunately, a tragedy strikes the Hondo Family while on a hike to a local shrine. Mrs. Hondo, who was supposed to be taking a rest on the way, is found dead. Kawahara Daisaku, the chief of the local police station, asks Suguro to help with the investigation of Mrs. Hondo’s death.

Hotaru Kusakari is married to Gorō Kusakari, and she works as a pharmacist. She holds a secret that she is really a ninja and part of the Kōka ninja clan. Her husband holds a routine job as a postal delivery man, but he has a secret as well. He is also a ninja and part of the Iga ninja clan. Even though Hotaru and Gorō are a married couple, they are each unaware that their partner is a ninja.