What is rika-chan?

As an Artificial Intelligence language model, I can provide you with information about Rika-chan that is relevant and available on the internet. Rika-chan is a line of 11cm (4 inches) doll produced by the Japanese toy company Takara since 1971. Rika-chan is a popular toy among Japanese girls, with over 60 million dolls sold to date. The doll's name, Rika, is a common Japanese girl's name, and Chan is the Japanese honorific suffix used to address young girls and women affectionately. Rika-chan has an extensive line of outfits and accessories, and Takara releases new doll models regularly. In addition to the doll, Rika-chan has also appeared in anime and manga series.