Karigal

Nie Mozuno is a small, timid boy with a weak personality, often targeted by delinquents or stumbling into open manholes—just a typical "prey" type with a knack for attracting trouble. One day, Kakao, a dark-skinned gal who's clearly his polar opposite, enters his life. With her loose-fitting uniform, a chest that seems ready to burst, and surprisingly well-defined abs, she takes an interest in him, calling him "prey" and making him the target of her "hunt"...!?

(Source: Akita Shoten, translated)