Seeing Koharu's crying face lowkey destroyed me.
Kouhei is a good dad. I feel most parents in his position would've immediately called the school or started confronting other parents. That was his initial instinct too, but he caught himself. What really sets him apart is that he didn't forget the actual child in all of this. He prioritized comforting Koharu and easing her pain instead of escalating a situation that could've gotten worse.
He didn't tell her to tough it out. He gave her the one thing she desperately needed. Comfort from the person she felt safest with, her only ally in that moment. He also gave her a healthy place to direct all that emotional energy. In most cases, stopping your child from going to school isn't advisable but I think in this specific situation it was good for Koharu. W parenting.