I love how there's the subtle detail that other passengers are as engaged in this whole relationship as our three MC commentators (the OL, The Manager, and the Uni-Student). On Page 14, behind the female friend, you can see some random background character is as shocked as everyone else, and it's clear because he's also invested in this story.
I half suspect that the ending of the series will be EVERYONE in the carriage getting involved and helping out the two lovebird MC's getting together.
