After a brief flashforward to the interrogation room, we return to our regularly scheduled school day, except that it's not! Joker's evil app is back and somehow it has taken Joker and the other student to a castle where the school used to be. (Right after accusing the volleyball teacher of thinking he's "the king in a castle".)

Some armored monsters imprison them both, leaving them to panic while listening to screaming from presumably tortured people.

The king of this castle is -- wait for it......... -- Kamoshida-sensei the pervy volleyball king! He is wearing fuzzy slippers and a too-short bathrobe with a heart pattern and not much underneath it. Like, a thong? I guess it's good to be the king.

Anyway, we're going to be executed, after some more child abuse.