She and her family are fans of the essays and novels written by Seishin Muroi, and is the reason they moved to Sotoba. Sunako dislikes people calling her name with the honorific "chan". It is later revealed that she is the leader of all the shiki in the village and is over 100 years old. In the final episode, she escapes the village with Seishin.
Voiced by: Aoi Yūki