Nana and Ryouta are neighbors, and the Kise and Hoshino families are friends. So they often meet on gatherings and they even went to kindergarten together and grew up together. She calls Ryouta, Ki-kun while he calls her Nana-chan. They have different group of friends but still communicates with each other. She's been into ballet eversince she was 5 years old, but Ryouta was not aware of it until they reached 10 years old when Ryouta was invited by his mother to watch Nana's ballet recital. Ryouta does not want to because he is not interested but was forced by his mother so he has no choice but to go. It was the first time he watched Nana do ballet and was amazed at how great and graceful she was and ever since then Ryouta calls her Nanacchi.