If the engine is small enough, it doesn't need a dedicated compartment. It's not from Japan, but from Hungary, but have a look at this, it can move on its own:
https://hu.wikipedia.org/wiki/Bzmot#/media/File:Bzmot-268_sp.jpg
@FlashyGrasshopper Wow that's cool but i still wonder where is the engine on such a thing. I can see no exhaust port on the train. No Wikipedia link either except in hungarian.
Oh, she is jealous of the two girls being in class 2, but she doesn't mention being jealous of him... I wonder what is in class 2 that makes her jealous that she can't be there? Hmmm.... I wonder...
I try to pinpoint all places that are shown in this manga. I have visited Japan several times before but I haven't been to the places that are mentioned in the manga.
@pomodoro Me neither, this manga's been showing us many hidden gems of Japan. I wonder if the Japan National Tourism Organization is sponsoring the author...