Mamoru's partner and friend since their days in the academy where they along with Kurogane comprised the previous generation's 35th Platoon. Mamoru's easily excitable and laid-back nature was compensated by Iori's hardworking and calm disposition and their relationship was further emboldened at how they were the only two survivors of the platoon's original graduates.
The captain of the EXE who Mamoru knew since his academy days. While Mamoru states at how Kurogane was his Platoon leader during his first-year, the latter was assigned as Student Council President and only "knew" Mamoru for around a year in the same platoon. Even with this comparatively small time together, Mamoru was inspired by Kurogane's strength and dedication and he aspired to be like him. Even after he and Iori entered the EXE's service, he referred to Kurogane as his senior as if he was back in the academy. This admiration however turned out to blind him to the ideals Kurogane truly followed as on the outside, Kurogane dispensed the law of the Inquisition while in reality, Kurogane more closely followed a personal ideal that happened to be in line with most of the Inquisition's actions preceding Sougetsu's moves to bring them closer to war. Ironically, Kurogane's backstory revealed that he was similar to Mamoru in a way of how he also disillusioned by his mentor's teachings when he betrayed his expectations.
Mamoru's immense nostalgia made him extremely friendly to the members of the current 35th platoon. He particularly greeted and introduced himself and apologized at how the circumstances had them face each other and recognized Ouka from the confusion.