A very rich girl (as seen in her designer accessories from Gucci, Cartier and Prada) Kouda is at first a rival to Eriko's group, but she quickly becomes friends with them after they brag about going to school with boys. An "insider" (a girl who transfers from the junior high branch of the private school rather than passing an entrance exam, like Eriko and friends did, to get in) who uses her knowledge of the school ways to show the others the ropes. Kouda aspires to become a famous actress, using all of her energy to be as outrageous as possible, so as to leave a lasting impression. She has the habit of dressing in completely bizarre outfits to gain attention, only to change into more normal clothes a split second later.
She has a brother, Takeshi Kouda. She is often ridiculed because of her large forehead, leaving her with the nickname To-Bi-Rah, from Kyan, the Okinawan tour guide, and is constantly harassed for having a large forhead by Yuma's sister, Momoka. Kouda joins the Celeb Club, and has a large house.