>>106212748
Hinako feels trapped as a woman since her mother just rolls over for her deadbeat dad so she's a tomboy that plays alien games with Shu (her mother really has no choice since I don't think women can even have jobs in 60s Japan and good luck being a single mother of 2 or winning custody)
As she gets older her father gets a massive debt and sells her off in an arranged marriage to pay it off
She wants to escape her arranged marriage so she gets mad that Shu only sees her as a friend (which is what she always wanted earlier) since if he didn't then maybe he could marry her instead.
Turns out the person who bought Hinako was the kid she saved one time who had to move because he inherited the estate from his dead dad but he could never let go of Hinako and how he felt about her when he was younger
Since the boy (fox mask) had overbearing mother and was raised in a certain way to be the head of the family he had to give up all individuality to function as the head and he expects Hinako to do it too and insists she'll find happiness in it
The story is the two Hinako's, Hinako (fox mask) and Hinako Shimizu (the independent Hinako who doesn't want to live her life as some slave wife) fighting each other.
At least that's how I've been understanding it