:re Chapter 7

Sasaki splinters Serpent's kagune with his own, and the rest of the Quinx Squad finally grasp that Akira Mado had not exaggerated his strength. Impressed that Sasaki can sprout so many tentacles at once, Serpent kicks him, but the blow barely registers as Sasaki coils his kagune around Yukimura 1/3 to sharpen his assault. Serpent slips away and kicks again, this time driving a foot clean through Sasaki's torso and leaving him hurt. Shirazu and Mutsuki move to help, yet he waves them off, regenerates, and readies himself once more, startling Mutsuki with how abruptly his manner hardens.

Serpent admits he finds Sasaki far more interesting than the other Quinx, and Sasaki replies that the ghoul has no business knowing anything about him. His kagune evolves further, the tentacles growing keener than before, and he finally runs Serpent through the stomach, calling it his payback. When he strips away the mask, Nishiki Nishio is revealed beneath it. Nishiki jeers that wherever Sasaki goes, whatever he does, he will always end up powerless. Hearing himself called Kaneki, Sasaki reflexively answers with Nishio-senpai, thrown by the words, and Nishiki is let go while Sasaki spirals into a breakdown, screaming in distress.

Recognizing the danger, Take Hirako calls off the Serpent Investigation to focus on subduing Sasaki, and Akira drops him with an Rc-suppressant round from a sniper rifle. She tells him to work through his state slowly. In her own mind, Akira notes that Sasaki is the product of a kakuhou transplant carried out by the scientist Akihiro Kanou of Aogiri Tree, and that while the CCG must treat him as human, a kagune spinning out of control would see him branded a ghoul and possibly put down. She reflects that he risked himself to shield his squad, and that his manner of fighting has now burned itself into his subordinates, who will feel fear, awe, and even envy. Afterward, at CCG Headquarters, Sasaki is summoned to an S3 meeting for a private talk with his superior, Kishou Arima.

Sasaki defeats the ghoul Serpent and unmasks him as Nishiki Nishio, a face from Kaneki's past. Being addressed as Kaneki shatters his stability and triggers a violent breakdown, forcing Hirako to halt the investigation and Akira to sedate him with an Rc-suppressant bullet. Akira's inner monologue lays out Sasaki's origin as one of Kanou's transplant subjects and the fragile line he walks between human and ghoul. Sasaki is then called to a private meeting with Kishou Arima.

This early installment bears the Japanese title 昧人, romanized as Maindo, with the English reading given as Remind and the chapter itself titled People in the Dark. It ran in issue 2014-52 on November 27, 2014, and later appeared in the first volume of Tokyo Ghoul:re, placed between chapters 6 and 8.