Naru Narusegawa is a 17-year-old student and resident of the Hinata Inn that can be described as "one fuse short of a cannon" because of her extremely fiery temper and tendency to be very physical, mainly with Keitaro whenever she feels he's acting perverted. Of all the girls in the Hinata House, she is victimized the most by Keitaro's clumsiness which often results in her being naked, exposed in some fashion, or lying in very suggestive positions. Throughout most of high school she studied hard and became Tops in the nation on the college practice exams in order to get into Tokyo University. Because of her intense study regiment she became majorly short-sighted and has to wear thick "coke-bottle glasses" when not wearing her contacts. She developed feelings for Keitaro, however, was unable to admit it to herself or anyone else for a long time. Despite overcoming this and confessing her love, hitting Keitaro whenever he got "too close" had become involuntary and second nature.