Is Bullet/Bullet hentai?
No
Rated PG-13 (Teens 13 or older) on MyAnimeList and not tagged as Hentai.

ONA · 2025 · 12 episodes · PG-13 - Teens 13 or older
Anthropomorphic, Sci-Fi
In the near future, civilization has collapsed, and the world has become a wasteland. Despite their poverty, the people use remnants of past civilizations to lead resilient lives. Gear works in a junk shop while also retrieving stolen goods alongside Qu-0213, a robot with four personalities, and White Bear, a gambler. One day, Gear finds himself thrust into a once-in-a-lifetime job to steal an important item. They soon find themselves up against deadly assassins, heart- pounding car chases, and explosive battles. What Gear and his team do not know yet is that the item they stole holds a secret that could shake the very foundation of this world. (Source: Disney+)
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