These are what we call the 'YMMV items.' Things that some people find in this work. We call them 'your mileage might vary' because not everyone sees these things in the same way. This starts discussions in the trope lists, a thing we don't want. Please use the discussion page if you'd like to discuss any of these items.
Designated Hero: There's really very little to recommend Soichiro, save for pretty boy looks and the occasional twinge of guilt. Still, he's the guy we're supposed to be cheering for...despite starting all the trouble in the first place.
Jerk Ass Woobie: What he's supposed to come off as, once you learn his VERY convoluted backstory. Does it work for you? Eh, YMMV.
Values Dissonance: As well as the standard "could only be acceptable in a romance novel" Values Dissonance, a big part of the plot — Sumi is poor, and lives her life according to Japanese culture, while Soichiro is rich and very Westernised. They have vastly different opinions on things like wasting food and when to wear shoes.
What an Idiot: Soichiro, after your Ax-Crazy best friend attemted to kill himself and your wife, it is most definatly NOT a good idea to continue to let her be around him.
The Woobie: Sumi. Used by her irresponsible brother, promoted to parent, and resorts to prostitution to protect her family, only to end up in a rich but vapid and dangerous world where nobody is really on her side. It's like the writer gets off on causing her misfortune.