Kenshi gets dropped into a world designed to seduce him, then the show actually makes you care why he stays. The harem structure disappears the moment you realize each girl's loyalty costs her something real. It's ecchi that earns its romance by letting the action sequences and character development do the heavy lifting instead of just the fanservice.

Kenshi Masaki, a 15-year-old half-brother of the hero Tenchi Masaki, is taken against his will to Geminar, a world where nations fight their wars with Sacred Mechanoids, humanoid weapons first unearthed in ancient ruins. A mysterious group tricks him into piloting one in an attempt to kill Lashara, the young ruler of the Shtrayu Empire, promising this is his way home. He chooses not to kill her and is captured, and it turns out he was deceived by the very people who brought him there. Learning the truth, and struck that the pilot is a boy, something very rare on Geminar, Lashara decides to help him and makes him her attendant. In that guise he goes with her to the Holy Land, a heavily fortified academy that trains Sacred Mechanoid pilots, most of them women. His kindness and wide range of skills soon make him popular with the female students, while some of the male students grow jealous. All the while, the organization that fooled him is working in secret against the academy, and war threatens to engulf the whole world. The OVA mixes mecha battles and fantasy with comedy and ecchi humor.