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

TV · 1971 · 23 episodes · PG-13 - Teens 13 or older
Action, Adult Cast, Adventure, Comedy, Mystery, Seinen
A master of escape, disguise, and all the duplicitous arts, Lupin III has inherited the legacy of his grandfather, Arsène Lupin, as the world's greatest thief. Along with his loyal partner, ace gunman Daisuke Jigen, Lupin leaves no jewel unplundered and no secret unexposed. Meanwhile, the alluring Fujiko Mine has Lupin wrapped around her finger and feels no qualms about using her charms to betray him whenever it suits her. Pursued endlessly by policeman Kouichi Zenigata, Lupin and his crew seek to take the world's riches for themselves despite the misadventures they experience along the way. [Written by MAL Rewrite]
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