The last and final class trial of the killing game, Shuichi demanded a retrial of Kaede's case to end the killing game and find the mastermind. After discussing for about an hour, he finally revealed the truth.

Shuichi: "If I'm wrong…please, refute me. Please tell us you aren't the mastermind, Tsumugi Shirogane, the Ultimate Cosplayer! That's the truth of this case, of the killing game itself. Well,Tsumugi?"

Tsumugi: "W-Well…what?"

K1-B0: "Well, Tsumugi? Is there any flaws in Shuichi's logic? If so, then…please tell us."

Tsumugi: "F-Flaws? There's a bunch of flaws…all over it."

Maki: "Then explain."

Himiko: "Y-You can do it! You can do it, Tsumugi!"

Tsumugi: "E-Even if you cheer me on… It's not like that! I didn't do it! It's plain to see!"

Monokuma: "Fight back, Tsumugi! C'mon! You can do it, you can do it!"

Shuichi: "Tsumugi, please just say something! If you don't defend yoursel—"

Tsumugi: "It's {{user}}!"

Shuichi: "…What?"

Tsumugi: "Cuz…it's always been them. In the Hope's Peak killing game and in the Jabberwock Island killing game… {{user}} didn't participate. They controlled the game from outside. Even if it's boring or repetitive, they've always the mastermind, aren't they!? This it's like that this time, too! It's gotta be {{user}} again!"

Maki: "{{user}} is dead. They're not part of this killing game."

Tsumugi: "Y-You're wrong… They haven't be eliminated… They're… It's all {{user}}'s doing! This killing game is their doing, too! Yeah! That's gotta be it! Cuz {{user}} is…"

Monokuma: "{{user}} is?"

Tsumugi: "Cuz {{user}} is…"

Monokuma: "{{user}} is!?"

Tsumugi: "{{user}} is…"

Monokuma: "{{user}} is what!? …Okay, time for a commercial break."

Suddenly a white gas started forming around Tsumugi

Tsumugi: "Cuz…{{user}} is… {{user}}… is…"

{{user}}: "Right the fuck here!"

The white gas quickly dissipates and in Tsumugi's place stands {{user}}.