Is Aquarion Movie: Ippatsu Gyakuten-hen hentai?
No
Rated PG-13 (Teens 13 or older) on MyAnimeList and not tagged as Hentai.

Movie · 2007 · 1 episodes · PG-13 - Teens 13 or older
Drama, Fantasy, Mecha
This movie is an alternative version of the TV series; it is composed of the two 2007 OVAs, edited to improve the pacing of the plot, and an extra segment akin to a TV episode where the cast are given the task of studying flowers. The plot has several differences to the TV series.
View on MyAnimeListShare
Check another title