Is Fushigi no Umi no Nadia: Original Movie hentai?
English title: Nadia: The Secret of Blue Water - The Motion Picture
No
Rated PG-13 (Teens 13 or older) on MyAnimeList and not tagged as Hentai.

Movie · 1991 · 1 episodes · PG-13 - Teens 13 or older
Action, Adventure, Drama, Historical, Mystery, Romance, Sci-Fi
Three years after the defeat of Gargoyle and Neo-Atlantis, a new threat has surfaced bent on bringing the world under his control. Geiger, using advanced robot technology, is attempting to begin a world war, and take control of the devistated world after the destruction has stopped. Once again, Nadia and Jean must fight to save the world, only this time from itself. (Source: ANN)
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