Arc Fatigue: The series falls dangerously close to Myth Stall after the major obstacles to Natsumi and Shoutarou's marriage are properly resolved, providing a volume's worth of material unnecessary to the narrative or filler that more-or-less rehashes the same theme of family unity until it nears the end.
Fridge Logic: Neither Shoutarou nor Natsumi seem to think to contact their banks and have the funds frozen — in Real Life it's very unlikely the con could withdraw or transfer more than a small fraction of it in time.
Periphery Demographic: The manga is officially designated seinen, but tends toward a softer art style and nuanced romance that would not be out of place in a shojo publication.
The Scrappy: Shoutarou's first wife abandons her children and severs all contact, leaving her sons very distressed, but the author never treats her as anything but sympathetic. When the family meets her late in the manga and she's pregnant again, many readers screamed for Child Protection Services to take the next baby away from her.
Tastes Like Diabetes: For some. Others will take this opportunity to indulge their respective sweet teeth.