Kao ni Denai Kashiwada-san to Kao ni Deru Oota-kun - Vol. 6 Ch. 65 - Kashiwada-san and Oota-kun on the Bullet Train

[MangaDex]

 

[Artemis0Fowl]

What what? The seats in the train turn???

 

[pir0zhki]

What what? The seats in the train turn???

On the shinkansen, the seats are mounted on a latching rotating frame that lets them be turned so that a group of four can face each other. Some local/long-distance trains with forward-facing seats have a similar system that's a bit simpler, in which you can simply move the seatbacks up and forward to reverse the seating direction. It's pretty clever. With this mechanism, the shinkansen can be "turned around" simply by rotating all the seats.