Saunoa is a Finnish word meaning the act of going to a sauna, and this slice-of-life manga follows a group of high school girls who bond over their shared love of the experience. The story centers on Kokage, a teenager who has never liked bathing and generally avoids Japanese public baths. Her perspective changes when she meets Lyydia, an exchange student from Finland, who introduces her to the world of sauna, at times dragging her along somewhat against her will. Through Lyydia, Kokage discovers the warmth and relaxation of the practice, and the group expands to include Serika, a self-described sauna enthusiast, and Maki, whose family runs a super-sento, a large Japanese public bathhouse with water park-like facilities that often include a sauna. Together, the four friends spend their days exploring different saunas and learning about the culture surrounding them. As Kokage grows more accustomed to this daily routine, Lyydias older sister Rumi arrives, leading the group into an even wider variety of sauna experiences. The manga, written by Hiroyuki Kasama and illustrated by Mosoko Miyatsuki, was serialized in Houbunshas Manga Time Kirara Max magazine beginning in 2023.