Rika Kayama, known as Licca-chan, attends elementary school, seeming like an ordinary girl until she learns she is the princess of the Doll Kingdom, also called Culture Fantasy or Fantasy Kingdom. This royal lineage comes from her mother, Queen Orie Kayama, who fled to the human world with Rika and her grandmother, Nanae Kayama, escaping the demon Devaul. Devaul seeks to kidnap Rika to usurp the throne, posing an ongoing threat.

Nanae provides Rika with a pink "Calling Ring" bracelet that alerts and summons the guardian Doll Licca during danger. This bracelet is later upgraded, allowing Rika to summon Doll Licca actively. The Doll Knights—Doll Licca, Doll Izumi, and Doll Isamu—transform from ordinary dolls into protectors, defending Rika and her friends from Devaul's agents like Dr. Scarecrow, Misty, and Dana.

Rika possesses a cheerful yet slightly impulsive personality. Her interests include singing, playing piano, baking, and window shopping. White and pink are her favorite colors, and she admires red roses. She attends either Shirakaba Gakuen Elementary School or Saint Terejia Gakuen, depicted variably as a third, fourth, or fifth grader.

Her family reflects a multicultural heritage: her father, Pierre Kayama, is a French musician, and her mother, Orie, is Japanese. Rika has younger twin sisters, Miki and Maki, younger triplets, Miku, Kako, and Gen, and grandparents on both sides.

Facing challenges, Rika relies on close friendships. Her best friend, Sumire Shinohara, gains a green bracelet to summon Doll Izumi, while classmate Dai Takabayashi obtains a blue bracelet to summon Doll Isamu. These allies join her defense, with Rika evolving from passive protection recipient to active participant.

In non-anime media, like the game *DreamMix TV World Fighters*, Rika wields the "Licca Turn," a technique draining life energy from opponents, often performed while embracing them. This portrayal exists separately from the anime's continuity.