Ransuke, a corporate slave who worked himself to death, suddenly finds himself transported to another world! Instead of fighting monsters or becoming a hero, he decides to pursue his greatest passion—saunas!Using magical flames for heat waves, chilling in enchanted cold baths, and discovering exotic herbs for the ultimate relaxation, he introduces the wonders of "isekai sauna culture"! But things take an unexpected turn when the beautiful women of this world—an elven maiden, a proud knight princess, a beastgirl, and more—get curious and decide to join him for some steamy "totonoi" (sauna bliss)! ――Isekai × Sauna × Slow Life!A slightly steamy (in more ways than one) fantasy adventure begins!