The Shifting Boundary (Season 1): Naoto starts as a near-recluse whose only solace is drawing private fantasy manga. When Nagatoro penetrates his safe space, she systematically strips away his defenses. The pivotal turning point of Season 1 occurs when the Art Club President threatens to abolish the club. Naoto refuses to surrender; backed by Nagatoro, he paints a vibrant portrait of her everyday self, triumphing in the public festival vote and earning a cheek kiss that dissolves their status as mere bully and target.
The Evolution into Mutual Support (Season 2): In 2nd Attack, their dynamic shifts from student/tormentor to mutual champions. When Nagatoro falls sick, Naoto overcomes his crippling awkwardness to nurse her at her home. Later, when Nagatoro faces defeat and crisis in judo, Naoto steps onto the tatami mat to train with her, inspiring her to challenge herself once more.
The Series Finale (2nd Attack Episode 12): During an aquarium "mock date," the unspoken tension peaks. Rather than retreating into teasing, both acknowledge their feelings without hiding behind jokes. They establish a mutual goal pact: when Nagatoro wins her judo tournament and Naoto passes his art entrance exams, they will share their true first kiss—ending the anime run with both characters standing as confident, equal partners ready to claim their future.