Rika is a young girl with black eyes and brown hair with pigtails. She wore a striped turquoise and purple shirt with a white hood.
After two years, her hair looks longer than before, and she has grown taller. She wears a dark colored apron with the Marine symbol and a striped dress with a hood. She wears black shoes and a bandanna tied over her head.
Rika was almost attacked by Helmeppo's pet wolf, but Roronoa Zoro defended her. Because Helmeppo saw this as a crime towards himself, he had the Marines imprison Zoro for thirty days.
Rika tried to thank Zoro by offering him onigiri while he was imprisoned, but he refused and told her to go away. Helmeppo then came in and took them away from her rudely, saying that if she gave them to Zoro, it would be as if she were the accomplice of a criminal. Helmeppo then spit the onigiri out complaining that they had sugar in them instead of salt. Rika replied saying she thought it would make them taste better. Helmeppo then ordered a Marine to throw her out, but luckily, Monkey D. Luffy caught Rika as she flew over the wall.
After Helmeppo left, Luffy talked to Zoro, who asked the pirate to feed him the stomped on onigiri. Zoro then asked Luffy to tell Rika that they were delicious. Luffy later passed on the message, and Rika explained the situation to Luffy and Koby.
Rika complimented Luffy after he punched Helmeppo, but Rika's mother ushered her away from the pirate. However, after the pirates defeated Marine Captain Morgan and Helmeppo, Rika and her mother fed Luffy, Zoro, and Koby as thanks for saving the town. Rika watched as the Marines requested the pirates to leave town. Koby refused to leave with Luffy since he wanted to become a Marine, and Rika and her mother watched in shock as Koby and Luffy punched each other.
After the timeskip, she appears to be more mature, and is training at the Marine base in Shells Town to become a waitress. She seems to be much better at cooking, and is popular among the Marines. She also has a bounty poster of Monkey D. Luffy hanging on her workplace.
In Episode 2, Rika is seen bringing food to Zoro which the food in the original anime was Riceballs. However in the 4kids' edits, the riceballs were changed to three cookies. Also, when Helmeppo took one and ate it, the third cookie was still in place when she offered them to Zoro.