Is Kidou Senshi Gundam: Suisei no Majo - Prologue hentai?
English title: Mobile Suit Gundam: The Witch from Mercury - Prologue
No
Rated R (17+ (violence & profanity)) on MyAnimeList and not tagged as Hentai.

Special · 2022 · 1 episodes · R - 17+ (violence & profanity)
Mecha, Sci-Fi, Space
On the planet Mercury, the advanced technology of cybernetic prostheses has led to the development of giant pilotable robots. However, prolonged use of these achievements in bioengineering takes a significant toll on a pilot's body. As the Merucians' mobile suits gain formidable power, fear rises among the people of Earth. On her daughter Ericht's fourth birthday, pilot Elnora Samaya tests the state-of-the-art Gundam Lfrith under the watchful eye of its creator, Cardo Nabo. Ericht visits Elnora at work despite orders not to, and chaos unfolds after she forms a strange bond with her mother's mecha. [Written by MAL Rewrite]
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