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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