Mr. Morning

From the mangaka of Amatsuki:
The Rainbow Stone Train crosses straight through a vast continent.
Newbie train crew member Toy is posted to work in Morning, the train carriage which charges the cheapest ticket prices!”
Torquay Toy (the nephew of the head-conductor of Morning) wants to work on a train powered by rainbow stone, but ends up working on the “Morning” section, which is reserved for the lowest class passengers.