Is Dr. Stone: Science Future hentai?
No
Rated PG-13 (Teens 13 or older) on MyAnimeList and not tagged as Hentai.

TV · 2025 · 12 episodes · PG-13 - Teens 13 or older
Adventure, Comedy, Shounen
Having resolved the crisis in the Petrification Kingdom, Senkuu and his companions gear up to deal directly with the mastermind behind the petrification phenomenon—who supposedly resides on the moon. The ambitious spaceship project, however, requires immense manpower and critical resources scattered across the world. Thus, the Kingdom of Science exploration team kick-starts its transcontinental journey on the ship Perseus to gather them all. Equipped with modern technology and bolstered by the new, capable members in their ranks, the exploration team feels confident about setting sail to their first destination: America. They soon realize that the region now hosts adversaries controlling the resources they need, doing so with scientific technology which rivals and even exceeds their own. In a battle of science versus science, Senkuu and his team must outsmart their rivals if they are to have any chance of ensuring the continued survival and rejuvenation of humanity. [Written by MAL Rewrite]
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