Bring It On! Vol 2

Bring It On! by Baek Hye-Kyung. A Romance manhwa rated Teen, published in English by Ice Kunion.

Mi-Ha is a fiercely competitive girl who never backs down from a challenge, and her rough-and-tough attitude scares off every boy around her, exactly as her protective older brother intended when he spent six years drilling her like a soldier. Then Sung-Suh transfers in: handsome, confident, and determined to win her over. Can this charming newcomer tame wild Mi-Ha, and will her brother ever allow it? A lively Korean romantic comedy.