This is a full-color manga page with a vertical split in a 7:3 ratio, set in a bright school classroom with desks and chairs. Panel P1 is a medium eye-level shot. On the left, a slender girl with long black hair and a youthful face wears a school uniform with a necktie; she stares at the other girl's chest with a flat, unimpressed expression. To her right, a taller, big-sister-type girl with blonde hair in a matching uniform and necktie stands calmly, facing forward. Panel P2 is a close-up in a stylized, chibi-deformed art style. The black-haired girl, now with teary eyes and a pout, is positioned on the left, swinging her small hand to slap the blonde girl's large chest. The blonde girl on the right maintains a cheerful, smiling expression as her chest bounces from the impact. The scene is rendered with soft, cute linework, gentle cel-shading, and a pastel color palette typical of a manga color page.
overlay effect: In the bottom panel, a 'ぽよーん' SFX is placed near the second girl's chest to indicate it is shaking.