Itsumo Dokodemo Nin2 Ninja

is a Japanese light novel series written by Taro Achi, with illustrations by Sumi Miya. The series began publication on April 10, 2003 by ASCII Media Works under their Dengeki Bunko publishing imprint.

Synopsis
Nice to meet you. I'm Makoto Kasuga, a second year student at Sunflower High School. My parents went abroad because of my father's work. After all, living alone is lonely, so I wondered if she could eat meals and watch TV with me, but suddenly I ended up living with a girl ... No, I'm not her. Besides, the daughter is a ninja. Isn't that also a time slip from the Warring States period? What will happen to my life that was peaceful and safe !?