Seta Kaoru is the guitarist of Hello, Happy World! She is very popular with ladies, whom she dubs her "little kittens" or whatever she may dub them as. She a tall girl with angular facial features, slanted crimson eyes, and long purple hair worn in a ponytail. She has chest-length forelocks and bangs that frame her face with a single lock that hangs loosely between her eyes. A flamboyant actress, Kaoru has an extravagant personality and is very intelligent and smart too.