Ichiban!!! is Yoshikawa Arata¡'s story of Umezono Hinako who has transferred to a new school during the third semester of her second year of junior high. Hinako¡'s only wish is that she finds girlfriends at her new school because she had trouble making friends at her last school. Much to her dismay, Kaiou Daifuzoku Junior High used to be an all boys' school and there are only three girls in her class, including her!