Nagatoro Saya

Naoki's younger sister who lives nearby. Yuki calls her "saya-mama" and adores her. She has a cheerful and open personality. She is a career woman who competes with thousands of writers from all over the world. She is an editor for a magazine.

She has a slender build with slightly small breasts. Instead, her butt is quite large. She has been in relationships but never got married. She is currently single.

She and Sachiko are good friends and have continued their friendship even after the couple divorced. She offered Yuuki and Shouko emergency shelter when the couple's relationship became difficult.

She gives legitimate criticism instead of praise to illustrations drawn by Yuuki. She often models nude for him for drawing practice.