Shortly after, Naito and his students arrive at their destination. He tells them they’re heading to the underground area beneath Uruda Temple — which sounds cool and mysterious — but the mood takes a sharp turn toward confusion when they stop in front of… a normal-looking restaurant. The students exchange looks like, “Did we just get tricked into lunch?”
An old lady appears at the entrance, lifts the curtain, and says she’s been expecting them (which is either comforting or extremely creepy). She leads them into her cozy living room… and then casually reveals a secret underground passageway leading straight to Uruda Temple. Just your average grandma stuff.
Meanwhile, elsewhere, Tsubakiri — captain of the Mamotero Agency — has just wiped out an entire squad of Oni, assisted by his ever-loyal (and perpetually exasperated) vice-captain, Yumogi. She’s annoyed because Tsubakiri didn’t just defeat the Oni — he obliterated them, which means she’ll be stuck cleaning up the mess.
Tsubakiri, however, defends himself with the casual tone of a mad scientist: he simply can’t resist “experimenting” on Oni whenever he encounters them. This time he’s mildly disappointed because there were only male Oni, and he prefers using female Oni for his tests, claiming they have higher pain tolerance. (Yes, he’s both sexist and creepy.)
Yumogi points out that his experiments have gotten a little… unhinged, especially his latest Frankenstein creation — an ugly hybrid of a dog, a monkey, and a pheasant. Tsubakiri admits it’s hideous, but insists it’s his crowning achievement: an Oni-eater that only preys on other Oni — the “ultimate anti-Oni biological weapon.”
Yumogi tries to steer him back to reality, reminding him that their mission is to protect civilians and destroy dangerous Oni — not to play Pokémon: Corpse Edition. But Tsubakiri is more fascinated by Oni blood — its healing abilities, its mutations, and the weapons it can produce. Yumogi reminds him that he’s only allowed to run these twisted science projects because of his agency membership, and maybe — just maybe — he should contribute to the actual mission once in a while.
What neither of them realizes is that a small Oni boy is hiding nearby, overhearing every horrifying word. The agents’ voices fade, and the boy breathes a sigh of relief… until Tsubakiri suddenly pops his head out like a jump-scare, grinning that he’s just found a “child specimen,” which he’s been running low on. (What a wholesome guy.)
Before he can act, Yumogi steps in and kicks the boy hard, trying to knock him out — but the kid remains conscious, stubbornly trying to get up. A drop of his blood splashes onto Tsubakiri’s uniform, and Yumogi immediately realizes this is bad news. Tsubakiri begins kicking the boy too, explaining that while Oni blood fascinates him scientifically, he’s still disgusted by it.
Then, to really prove he’s a walking nightmare, Tsubakiri uses his ability — manipulating black bacteria — to control the corpses of the fallen Oni, merging them into a grotesque mountain of flesh and crushing the boy underneath until he dies. His black bacteria powers let him control corpses without any limit, unlike most agents who use them for weapons or spore attacks.
Finally, he orders his ugly hybrid monster to eat the pile of Oni remains like it’s some kind of grotesque clean-up crew. With the mess handled, Tsubakiri and Yumogi get back to “work” — which in his case, mostly means thinking about more experiments.
Back in the underground tunnel, Naito and the students keep walking until they reach a huge door. He opens it with a flourish, revealing the Oni Agency Kyoto Base — which is so enormous that Shiki and the others mistake it for a mansion.
Just then, a guy with pink hair strolls out of a room. Upon spotting Naito, he approaches calmly… until he notices Kuina among the students. In a split second, he transforms from cool agent to lovestruck teenager, frantically fixing his hair before boldly asking her for her number. Kuina, with all the grace of a professional heartbreaker, declines.
The rejection hits the pink-haired flirt hard, but Kyouya doesn’t lose hope — in his mind, love is a marathon, not a sprint. One day, he’s sure, luck will be on his side. Shiki, still trying to figure out who this clown is, asks. With a grin, Kyouya introduces himself as the commander of the Oni Agency’s support unit and, oh yeah, an old classmate of Naito back at Rosette Academy.
Naito quickly shuts down the reunion vibes and informs everyone he’s heading to the front lines. His students perk up, eager to tag along, but he ignores their enthusiasm and instead tells Kyouya he can “use them however he wants” until he returns. (The students are silently wondering if they’ve just been volunteered as free labor.)
Before the moment can get more awkward, a nurse rushes in with an emergency report. She notices the academy students and orders them to get changed quickly — they’re going to need all hands on deck for this operation. Moments later, everyone is in uniform and heading to the patient center.
Shiki looks around and shudders. The place is packed with injured frontline soldiers, and the air is thick with urgency. The nurse calls Kyouya over to a soldier in especially bad shape — both arms and legs gone, lungs shredded, barely breathing. She estimates the man has about three minutes left.
Shiki is horrified. Life on the front lines suddenly feels far scarier than any training drill. But Kyouya, smiling like he’s about to perform a magic trick, tells the patient he’s going to be fine. Shiki protests, insisting there’s no way this man survives. Kyouya just tells him to trust him, then orders several Oni blood bags to be brought over, promising everyone a “front-line reality show” demonstration.
Meanwhile, Tsubakiri and his team have just crushed the first wave of Oni agents. The survivors, watching their commander and vice-commander drop like flies, start wondering if running away is the smarter career move. Tsubakiri walks toward them, clearly intending to finish the job… until Naito arrives at the last moment.
Naito unleashes his Blood Eclipse Release, summoning blood archers that rain arrows down on Tsubakiri. But the captain blocks the attack with the corpses of fallen Oni, using them as shields like the world’s grimmest umbrellas.
With that little spat out of the way, Tsubakiri casually mentions hearing about a place where Oni have been quietly gathering, wondering aloud if wiping it out would mean the end of the species. Naito has no idea what he’s talking about, so Tsubakiri shrugs it off as just another rumor.
Back at the agency, Kyouya hooks several Oni blood bags to his own body before turning to the patient. He asks whether the man wants arms or legs first. Given the lung damage, speaking is out of the question, so the soldier mouths his answer — arms first, because if he lives, he wants to hug his kids again.
Kyouya reassures him, promising he’ll make it back to his family. Then, with a scalpel, he slices into his own skin, letting thick Oni blood flow into the patient’s mouth. The man screams in pain, forcing nurses to order the students to hold him down.
Seconds later, the blood packs run dry, and the nurse sends a few students to fetch more. Shiki keeps holding the patient — until he notices something that makes him stumble backward in shock. The man’s arms are growing back. Cell regeneration has kicked in, his lungs are slowly repairing, and his once-hopeless condition is reversing right before their eyes.
The students watch in stunned silence as the soldier’s arms and lungs fully heal before their eyes. Shiki, still trying to process the miracle, asks Kyouya if the man’s legs will regenerate too. Kyouya nods, explaining that they will — but only with time and the right medical doses. If they tried to regenerate arms and legs all at once, the patient’s body could develop antibodies, making future Oni blood transfusions useless.
The man will probably have to retire from the battle unit, but Kyouya tells him he can still join the support team if he wants to help the agency. Overwhelmed, the soldier tears up, thanking Kyouya for saving his life. Turning to the students, Kyouya reminds them that in this war, the man they just saw could easily have been any one of them. He understands their eagerness to fight on the front lines, but he points out that frontline fighters survive because there’s always someone watching their backs — and that’s exactly the support unit’s job. The students, now impressed, offer to help however they can.
Kyouya already has a “perfect” task for Shiki — babysitting duty. He points to a little girl named May, who arrived the day before after being attacked by a “Mama” Oni. Her parents are still missing. Shiki sits beside her and tries making small talk, but she ignores him until he asks if she wants to go to Urauda. She says she doesn’t know where that is. Shiki is baffled — everyone learns about Urauda in elementary school — but May explains she’s never been to school.
As they walk down the hallway, a grim sight passes them: a new batch of Oni corpses from a recent battle. May stares at the bodies, and then freezes — two of them are her parents. She breaks down, crying over their loss.
Meanwhile, on the front lines, Tsubakiri (with that “I’ve got a nasty idea” smirk) tells Naito that he left several Oni corpses laced with his bacteria behind. He figured the enemy would haul them back to base — not realizing they were basically delivering him remote-controlled zombies. Naito’s eyes widen as the horrifying implication sinks in.
Tsubakiri isn’t sure if the corpses have reached the agency yet, so he decides to test his control by moving his fingers. Back at the agency, May’s father’s corpse suddenly sits upright. Overjoyed, May thinks her dad is alive — until he grabs her by the throat. Shiki and Kyouya rush over, and Kyouya instantly realizes this is Tsubakiri’s doing.
He orders Shiki to cover May’s eyes, then swiftly drives two scalpels into the corpse’s skull, destroying the brain and ending the attack. In cases like this, decapitation alone won’t work — you have to take out the brain.
May, devastated, clings to her father’s now-lifeless body, sobbing. Kyouya feels the weight of her grief but quickly realizes the bigger problem — there are over 30 other corpses in the building, all under Tsubakiri’s control.
