

The story follows a Roman architect named Lucius, who is having trouble coming up with ideas. One day, he discovers a hidden tunnel underneath a spa that leads him to a modern Japanese bath house. Inspired by the innovations found there, he creates his own spa, Roma Thermae, bringing in the modern ideas to his time.
Lucius

Mami

Hadrian

Ceionius

Antoninus

Noboru Itami

Marukusu

Shuzo Yamakoshi

Tateno

Yamakoshi Shuzo

Yumi Yamakoshi

Kishimoto

Saburo
Middle-aged man at bath

Michiko Hirai

Ujino

Showroom department head

Nagura, the Elder

Mogami, the Professor
Onishi, the egg lover
Uncle at the Public Bath
Michiko's Dad

Old Lady at Fertility Festival
Lady at Fertility Festival
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Livia (voice)

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