Ironic, but the Japanese salary man culture of 100+ work hours a week is almost mandatory.
A guy getting married is pretty much going from kareshi straight to karoshi in a matter of months and they can forget about having kids.
Tragically cruel and depressing how capitalism has driven fun and reproductive behavior out of healthy people instead of more free time for every educated person and dividing work into flexible work-life balance.
Sigh, but I digress.
This is a cute manga and worth a follow in my opinion.