|Full Name: Nagi Matsuo|
|Ranger Designation: Ki Ninger|
|Gear: Ninja Ichibantou, Gamagama-ju, Karakuri Hengen|
|Otomonin: Dumpmaru, Genbumaru|
|Nagi is a very friendly young man. He might not seem like it but is very observant and street smart. He is obsessed with getting licences and certifications for different things to make good use of. Knowing of his grandfather's title as the Last Ninja, he decided to compete against his teammates to inherit it, thinking the title would help him in looking for jobs.
Like most Nin Ningers except Takaharu, he initially refuse to become a Nin Ninger, having no courage until Takaharu encouraged them. At first he tried to use textbooks as guidances but having none them helped him in against Youkai Kasha, he decided to use his experience instead, taking Takaharu as an example for not thinking over his actions first. One of Yoshitaka Igasaki's successors, Nagi was one of his grandchildren chosen to become the Nin Ningers as Ki Ninger, the Agile Ninja. He was called by Tsumuji Igasaki, his uncle and Takaharu and Fuuka's father to their dojo, which much later turned into a pile of ruins by Hitokarages.
After the final battle against Gengetsu Kibaoni, Nagi studies to get into university.