Ayaka Nanakura is a supporting character in Pseudo Harem, best known as the younger sister of the main heroine, Rin Nanakura. She is an elementary school student, which places her at a notably younger age than her sister and the other central characters. Her birthday is on March 25th. Physically, Ayaka is depicted with pink hair that falls to her neck and red eyes.

As a much younger sibling, Ayaka receives a great deal of affectionate attention, not only from her older sister Rin but also from Rin's senpai, Eiji Kitahama. While her status as the "little sister" defines her initial role, she demonstrates a more complex side when interacting with people her own age. In these situations, Ayaka shows a personality that she has inherited from her older sister, hinting at a playful or expressive nature that mirrors Rin’s own theatrical tendencies. Her role in the story is primarily to provide wholesome family interactions and to occasionally showcase a dynamic that complements the main relationship between Rin and Eiji. Over the course of the series, as Rin and Eiji’s relationship develops, Ayaka remains an important part of their shared world, eventually growing up and pursuing a career as an actress.