Dr. Haruka Nishikikoji works at a children's health center at Nanahoshi Elementary School. Beneath his stern demeanor, he has a kind and generous heart. Besides working as a Doctor, he loves to devise “dream inventions” such as “good-cheer helmet” which makes you happy all the time, and his “kissing lipstick” which makes everyone want to kiss you. Of course, most of those inventions turn out to be total failures, but that never discourages him. The genius doctor always believes that his next inventions will really work, and hopes above all that they will help the people who need it the most.