Zenbu Kudasai, Senpai.

Sakura Chiyoda is a girl who loves judo, and she works as a student manager of the school judo club. She happens to see a junior boy, Dosaka, who seems like a promising judoka, and she scouts him out for the club. However, he summarily rejects her offer, dismissing it as unrealistic "youthful enthusiasm." Sakura, however, is not ready to give up, and offers him a “contract” to join the club. But a dangerously sweet trap awaits her.... (Source: Ichijinsha, translated)