Main character from "Secret" Arc.

 

A 17-year-old boy in his senior year of high school. Often thickheaded and clumsy, but also dependable and sometimes cool, despite his usual dorky demeanor. As the story progresses, he receives favorable attention and romantic feelings from the many girls he knows, but only has eyes for Sakuraba Yurika.

His most important secret in the manga is that when he sneezes he becomes a girl with blond hair and a somewhat underdeveloped body with a 'cute' charm. This leads him to get into some unfortunate (and hilarious) situations. He originally uses his female form to successfully become friends with Sakuraba Yurika and continues to use it when he feels like being with Yurika. He resorts to using a 'koyori string' to make himself sneeze and become a girl whenever he pleases.