As the kagune punctures Ogata’s torso and kills him instantly, the perpetrator is revealed to be a janitor who currently works for the school. The boys recall seeing him before, to which he declares his name to be Tanaka, working at the school for several months though it was hard to move around freely. Since the janitor is a ghoul, it is believed that ghouls may exist within the school compound as well. Fura suspects Tanaka to be the ‘Lantern,’ who killed his friends, and decides to charge toward him only to be kicked away by Arima. Arima reminds him that weapons like his don’t stand a chance against a ghoul’s kagune. Taishi questions Arima’s ability to defeat a ghoul, but Tanaka commends his splendid agility in combat. The ghoul doubts Arima’s capability to win against a ghoul, to which Arima suggests that it’s the appropriate time for “Yukimura 1/3” to be put to use.
Arima suddenly opens his guitar case, unleashing large capsule which transforms into a sword-like device. Tanaka is taken aback, and proceeds to deny the questionable tool that Arima held. Arima charges towards toward Tanaka, slicing off his kagune. He then explains to Taishi that Yukimura is a quinque; an anti-ghoul weapon made from kagune which is the raw-material, since it’s the only form of matter that can challenge a ghoul. Arima continues to segment Tanaka’s body, cutting him entirely in half. Arima reveals himself to be a Ghoul Investigator; which is the reason as to why he possessed a quinque in the first place.
After paramedics arrive to remove the body, Marude thanks Arima for his job, but lectures him for doing an undercover investigation single handedly without the permission of his seniors. Taishi compliments Arima’s bravery and strength in defeating the ghoul as an investigator. It is made known that Arima had only attended the school for the sake of pursuing ghouls, and had decided to drag Fura into the investigation as well. He then thanks Fura for his company, mentioning that he’d be leaving the school to go elsewhere and investigate. Taishi becomes infuriated, knowing that Arima would never be able to live a normal school life, and decides to keep his true identity a secret. He implies that Arima stay in school to ‘live normally’ for a little while longer, to which Arima agrees.
However, “Lantern” is not dead as yet, but this case seems to be a challenge due to the ghoul’s special kagune and extraordinary strength.