Heroine Hajimemashita.

Shuko Kodakamine is strong—too strong, by the standards of some. She hopes to make a good high school debut, but that plan goes up in smoke almost immediately when she injures the attractive, charismatic Serizawa-kun...and later suplexes him, to boot! But when Serizawa-kun finds himself in hot water with a jealous boyfriend, it's Shuko who comes to his aid...and he comes up with a ridiculous proposition: If Shuko becomes his bodyguard, he'll make her the most important girl in his world!

(Source: Kodansha USA)