The story shares some character names and general terms from the anime Photon, another series created by Masaki Kajishima.

Kenshi Masaki is a 15-year-old boy that has unwillingly traveled from his home on Earth to the alternate world of Geminar (ジェミナー, Jeminā).

On Geminar, the countries wage wars using Sacred Mechanoids, humanoid exoskeletal weapons that were originally discovered within ancient ruins and developed over centuries.

After being tricked by a mysterious organization into participating in an attempt to assassinate Lashara Earth XXVIII, the young ruler of the Shtrayu Empire, he ends up captured after he chooses not to kill her.

Disguised as her attendant, Kenshi travels with her and her bodyguard Chiaia Flann to the Holy Land, a virtually impregnable fortress that serves as an academy to train Sacred Mechanoid pilots (Mechamasters), most of whom are female.

[4] At Otakon 2012, North American distributor Funimation Entertainment announced they have licensed the series under the title of Tenchi Muyo!