Shiho comes from serious money—her father's a major company executive—and she's got the confidence that comes with it, though not always in a charming way. She's materialistic, tends to look down on ordinary people (literally calling them "the common masses"), and her go-to apology is throwing cash at problems.
She and Shindou go way back to childhood, which is where things get complicated. He turned her down romantically at some point, and she's never really moved past it. That rejection apparently lit a fire under her to actually work and prove something, despite not needing the money. But mostly, she channels that hurt into making his life difficult—using the fact that his father owes money to her father's company as ammunition to bully him. It's pretty obvious to anyone paying attention that she's still into him, but she can't handle expressing it like a normal person, so the teasing and cruelty is what comes out instead.
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