Yoshida, a bath architect specializing in traditional Japanese bathing facilities, accepts an unconventional commission to design a Roman-style bathhouse, drawn by the project’s novelty. His initial enthusiasm dims when the client’s specifications favor ostentatious elements—such as large-breasted female statues and a gold bathtub—over functional or culturally authentic design. During planning, he crosses paths with Lucius Modestus, a time-displaced Roman architect stranded in modern Japan. After Yoshida assists Lucius in returning a displaced koi to its pond, the Roman architect examines the bathhouse blueprints. Recognizing Yoshida’s struggle to reconcile Roman aesthetics with the client’s demands, Lucius proposes a collaborative redesign. Their revised plan merges Roman architectural principles with Japanese sensibilities, replacing the statues with a statue of Diana positioned beside the gold bathtub—a solution satisfying the client while preserving cultural coherence. Three months after the renovated hot spring opens, the project earns Yoshida widespread acclaim, cementing his ability to harmonize disparate traditions. His narrative underscores adaptability, cross-cultural collaboration, and the balance between artistic integrity and client expectations, culminating in professional growth through the synthesis of Roman and Japanese design into a unified vision.