Tsumuji Igasaki (伊賀崎 旋風 Igasaki Tsumuji?) is Takaharu and Fuuka's father, as well as Yakumo, Nagi, and Kasumi's uncle. He is the son of Yoshitaka Igasaki, the Last Ninja.
In his younger life, Tsumuji was known for being a ninja prodigy, being called Super Ninja (スーパー忍者 Sūpā Ninja?) having looked up to his father, the Last Ninja and dreamt of following his path. But once he entered his teenage years, his Nintality was stolen by Kyuemon Izayoi and his training was erased from his memories.Shinobi 16: The Father Tsumuji Is a Super Ninja!?
Tsumuji had called all five candidates of Ninningers to their clan's dojo, which was in ruins after several Hitokarages decimated it. Takaharu proudly accepted the mantle of Ninninger but the others refused. While on their way to Gengetsu Kibaoni's resting place, Tsumuji sensed "something off" until Gengetsu was released from his seal. The Ninningers took care of a Youkai and defeated it with their Shurikenjin. Afterwards, he met his father, Yoshitaka Igasaki whom was thought to be dead.
When the dojo is brought to the worldIcon-crosswiki of the Kamen Riders due to ShockerIcon-crosswiki altering reality with the History Modifying MachineIcon-crosswiki, Tsumuji is nearly erased from existence along with his father. He is saved when the Ninningers team up with Kamen Riders DriveIcon-crosswiki and MachIcon-crosswiki to destroy "Doctor D"Icon-crosswiki who orchestrated the plot, returning them to their own world. Shuriken Sentai Ninninger Vs. Kamen Rider Drive Spring Vacation One-Hour Combining Special
While not a ninja himself, he runs the Ninjutsu Dojo, where the Ninningers train their ninja skills. Aside from teaching them the basic of Ninja, he also wished to follow his father's path but unable to do so, due to lack of potential as a Ninja. Shinobi 6: Tengu's Spirit Away
Seeing the Ninningers needed more advanced training, Tsumuji called the previous red ninjas Sasuke/NinjaRed and Yousuke Shiina/HurricaneRed to teach them how to be true ninja. Shinobi 7: Spring Ninja Festival!
During Father's Day, Tsumuji revealed to his children about his past life as a ninja, and in fact, he was involved in their plan to take out Youkai Kasabake. After his part of the plan was done, Tsumuji was advised to take shelter but witnessing the Ninningers being badly beaten, his love and concern for his family temporarily spiked his Nintality, allowing him to reuse his Shuriken Ninpo: Tornado Technique and save them from Kasabake. However, his Nintality reverted back to its weakened state after the fight, leading the Ninningers to suspect it was a temporary power boost that was "a fluke". Shinobi 16: The Father Tsumuji Is a Super Ninja!?
After the Ninningers defeated the first of Kyuemon's Izayoi ninjas, Yoshitaka confided in Takaharu and Fuuka that the source of their power lay within the Igasaki's Nintality, revealing that the cause of the disappearance of Tsumuji's Nintality was infact due to it being stolen by Kyuemon. Shinobi 28: Race to It! The Kibaoni Ninja Squad
After reclaiming his lost powers thanks to the other Ninningers, Tsumuji joins forces with them in the final battle against the Kibaoni forces by transforming himself into his own version of AkaNinger.