Regulus, a diligent employee of Roman consul Lepidus, is assigned to aid architect Lucius Modestus in developing an outdoor bath near Mount Vesuvius. He directs Lucius to a volcanic well channeling geothermal heat, its waters pivotal to the project. Unbeknownst to both, the well enables Lucius to traverse time, arriving in modern Japan. Insights from Japanese hot springs inspire innovations in Roman bath designs, blending ancient and contemporary techniques. The completed baths restore Lepidus’s vitality, prompting his eventual marriage—a consequence cementing Regulus’s behind-the-scenes influence on the endeavor. No additional personal history or narrative context beyond this incident is recorded.