A nobleman, Reinart, is suddenly transported to another world—straight from his hotel bathroom, still wearing a bathrobe.
Meanwhile, science‑minded Shoko Ikeda buys a suspicious “Ancient King’s Gold Coin” at an online auction... and begins hearing voices.

Two strangers, each cast into the other’s world.
Their cross-world mix‑up sets history gently—but profoundly—off course.

One man mistakes a beef‑bowl restaurant for a sacred shrine, digs hot springs with geothermal magic, and is soon worshipped as the God of Geothermal Flame.
One woman cures an epidemic with sweet potatoes and basic science, only to be hailed as Lady Potato, the Sweet‑Potato Goddess.

What begins as two isolated misunderstandings blossoms into new civilizations—
and eventually, new myths.

Connecting their worlds is the Ancient King’s Gold Coin.
The voices exchanged through it become divine revelations.
Hot springs and sweet potatoes.
Science and magic.
Laughter and prayer.

In the end, the world is saved not by heroes or prophecies—
but by a few well‑intentioned mistakes.

A comedy that begins in bathrobe-clad absurdity and ends in legend—
“I Got Isekai’d in a Bathrobe and They Treated Me Like a God
—The Geothermal Mage and the Science Lady—”
The definitive myth of civilization born from chaos.