Ryōta Watari, captain of the Sumiya Junior High football team wearing jersey number 11, sports medium-length light brown hair swept slightly to the right and light caramel brown eyes, enhancing his reputation for good looks. His slightly disheveled uniform, featuring a loose tie and untucked shirt, reinforces his approachable, casual image.

Outgoing and friendly, Watari occasionally displays a frivolous streak, especially regarding romance, openly expressing interest in "cute" girls like Kaori Miyazono and Hiroko Seto. Yet beneath this surface lies deeper emotional insight and loyalty, particularly towards childhood friends Kōsei Arima and Tsubaki Sawabe. He comforts teammates after football losses and actively encourages Kōsei through personal struggles.

A core member of the friend group with Kōsei and Tsubaki, Watari's background includes thoughtful gestures, such as buying scented erasers for Kōsei's hospitalized mother. He facilitated Kōsei's initial connection with Kaori by agreeing to be set up with her, though this primarily served as Kaori's pretext to meet Kōsei. When Kōsei later confessed feelings for Kaori, Watari accepted it without resentment, advising Kōsei that romantic worth is determined by the recipient's choice and urging decisive action.

A proficient football player who easily dribbles past opponents, Watari sometimes gets distracted during games. Off the field, he shares philosophical perspectives like "Stars only shine when they’re set against the night" and "A man can only take action! Whether or not it’s impossible, the girl will let you know," guiding Kōsei’s emotional growth. His April 4 birthday aligns symbolically with springtime themes of renewal.

Maintaining a lighthearted exterior, Watari confronts vulnerability after significant football defeats, expressing frustration with determined cries of "Dammit! No way am I going to lose next time!" This highlights his resilience. He consistently provides comic relief and stability throughout the narrative.