Gun control in Japan has always been strict. So much so, that the only people with access seem to be law enforcement, and civil defense. Sure, some organized crime elements have been able to acquire some from time to time, but to be perfectly honest, even they have a hard time trying to bring guns into Japan, let alone buy them from dealers who somehow snuck them in. As such, you can probably imagine how insane it must have been when an officer patrolling a train car on the Kirishima Limited Express somehow managed to misplace a loaded gun. Whoopsidoodle.
After suffering a stomachache, the officer took his loaded gun off, placing it in a bag on his seat, then made way for the toilet. And here is where both the plot and chewing out that the officer received thicken. On the way to the restroom, he noticed the bag was missing. Gee, what an unexpected possibility.
They ended up finding the bag, complete with gun, during a final check of the train after it had gone to a different location for cleaning. All’s well that ends well, right? Tell that to his C.O.