Lucius Modestus, an ancient Roman architect, finds himself job-hunting due to having trouble coming up with new ideas. As his demeanor and personality become dismal, his friends try taking him to a bathhouse for him to relax. Unable to unwind in the bustling and crowded bath, Lucius dips his head in the water. Down there, he finds a secret tunnel that transports him to a modern-day Japanese bathhouse, providing him the inspiration he needed to make a new creation. Loaded with what seems to be knowledge way ahead of his time, Lucius does his best to try and recreate his findings, usually inferior in quality due to his circumstances. However, the sheer ingenuity may be just enough to gain the attention of the citizens and regain his reputation as an architect.

Lucius Modestus, an ancient Roman architect, finds himself job-hunting due to having trouble coming up with new ideas. As his demeanor and personality become dismal, his friends try taking him to a bathhouse for him to relax. Unable to unwind in the bustling and crowded bath, Lucius dips his head in the water. Down there, he finds a secret tunnel that transports him to a modern-day Japanese bathhouse, providing him the inspiration he needed to make a new creation. Loaded with what seems to be knowledge way ahead of his time, Lucius does his best to try and recreate his findings, usually inferior in quality due to his circumstances. However, the sheer ingenuity may be just enough to gain the attention of the citizens and regain his reputation as an architect. Note: MAL considers this show to be three episodes and not five. See More Info for additional details.

Bonus episodes included with the BD/DVD. The first episode consists of Miwaku no Farosu (Alluring Pharos) and Sanshimai OL Terumae Satsujin Jiken (The Three Sisters of Thermae Romae Murder Case). The second episode consists of Subesube ni Naritai (I Want to Have Smooth Skin) and Hitasura Suberitai (I Just Want to Slip).

Based On a Visual Novel developed by Minato Soft. Due to family troubles, Ren Uesugi and his sister, Mihato, leave their home. They end up moving to the city but find themselves with a lack of money. Somehow they are able to find work in the form of the Kuonji family's mansion, being employed as servants to the three sisters of the Kuonji family: Shinra, Miyu, and Yume. Being a servant also associates Ren with the mansion's additional servants and the Kuonji sisters' friends. (Source: Wikipedia)