The train they board is a mysterious train driven by "Denden," the spirit of the train.
This is a new type of work in which active VTubers/VSingers appear as "themselves".
The virtual existence of the "Den-Den" makes it possible for them to do "anything and everything", but it is the opposite of that, the talk is very human.
A short animation that will make you laugh with its mix of "aru aru" and unbelievable developments.