Is Sekiro: No Defeat hentai?
No
Rated R (17+ (violence & profanity)) on MyAnimeList and not tagged as Hentai.

Movie · 2026 · 1 episodes · R - 17+ (violence & profanity)
Action, Historical, Samurai
The time is Sengoku. Japan is fractured into many independent nations entangled in ceaseless war. At the center lies Ashina, a land of sacred earth and ancient mystery. Two decades after Sword Saint Isshin Ashina reclaimed the region in a brutal coup, a new threat emerges from within: The Interior Ministry. Desperate to protect his homeland, Isshin's grandson Gen'ichirou turns to forbidden powers. The only hope lies in a kidnapped boy—the Divine Heir—and his silent protector: a loyal shinobi known only as Sekiro. This is the story of a lord and his retainer—and their quest to restore balance to a nation on the edge. (Source: Crunchyroll)
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