Sumiharu Inukai/Plot

Background
As part of Ninomiya Squad, he suffered the penalty of having his Squad demoted to B-rank after Hatohara's violation of regulations.

Large-Scale Invasion Arc
He is briefly seen at Rinji's house following Hatohara's disappearance during Osamu's flashback.

B-Rank Rank Battles Arc
He is part of the four-way rank war between Ninomiya Squad, Tamakoma Second, Kageura Squad, and Azuma Squad. At first, he plays in the snow and is scolded by Tsuji. He tracks down Osamu and begins to fight him, forcing Osamu to flee into a school building, Inukai tells Osamu that both of them are faster so Inukai catches up to Osamu fast but Osamu was expecting that and planted an Asteroid trap but Inukai blocks it but praises Osamu for improving. However, Koarai and Okudera ambush him, cutting off his arm. Tsuji comes in to help out so the duo engages the two in battle wit the Azuma Squad duo. When Chika prepares to shoot, he says that there is nothing about which to worry since Chika does have the will to shoot. However, contrary to what he said, Chika shoots, but he manages to dodge since Chika's attack was slow and used the radar. Now knowing Chika's location, he pursues her, when he is sniped by Ema. Kageura appears and finishes him off. He accuses Kageura Squad of being too kind to Tamakoma Second. Kageura tells him to shut up and die. Inukai bails out.

Later, during the Galopoula Invasion, he shoots down Idras, following orders from his captain.