Arashi Waraino is a 16-year-old female high school student and member of the comedy duo JK Cool, represented by talent agency Yoshimoto Kogyo. Standing 155 cm tall and weighing 47 kg, she has a birthday on March 25 and blood type B. Her appearance features dark brown hair styled in a bob cut, rosewood-colored eyes, and a distinctive beauty mark positioned below the left side of her face. She typically wears brick red sunglasses, a green jacket with lime green accents on the sleeves layered over a white dress shirt and red tie, completed by black socks and dark mustard-colored sneakers.

Within JK Cool, she serves as the straight man, providing a reactive counterpoint to her partner Eru Kusaba's comedic antics. Her personality leans toward nervousness and fickleness, often causing her to struggle maintaining composure during their routines. This dynamic positions her primarily to react to her partner's humor rather than initiate it. Her surname "Waraino" stems from the Japanese characters signifying "straw," "boar," and "field/wilderness."