Well, I haven't seen anyone consider all the game analogies and the fact that actual memlord and game queen Saiko handy made an appearance yet. Maybe it's the end credits to Furuta's game and the start of a new one. She could just show up and be like "hey, the main character of a game usually has 3 lives. New chance! Take it sensei!"
She's been his Twitter icon before right? I cannot believe someone Ishida loves so much as a character won't be used to narrate. Everyone he really pays attention to (cover art, official art, twitter icons) has been a main narrator of Tokyo Ghoul. I dotn think he'd end it without using her.
Another catalyst is Hide. Pretty sure the sneaky bastard had something planned. He's a lot like kaneki in that he will prioritize the things that matter most to him and kaneki, so all this tragedy may seem like a necessary evil to win the game. After all, he didn't return to the manga only to see its end.
Furuta's accomplished his plan, it seems like he's announced that its Game Over, and it makes sense if he's the one who implies the next chapter is the end credits. But there are still players left who haven't been used. Shiny untouched chess pieces left over from Kaneki's tendency to keep leaving his loved ones behind. Urie, Saiko, Mutsuki, maybe even the zombie child. Amon, Akira, those who chose to be removed from the narrative. Uta and Hide, who seem to still have some plans left from unknown motives.
Maybe Kaneki shouldn't be a narrator. Maybe the narrative should shift, because if seen through kaneki's perspective, things will always be tragedy.
Third time's the charm right? Kaneki has been defeated 3 times right? You got one life left, bro. Last chance.