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

TV · 1999 · 62 episodes · PG-13 - Teens 13 or older
Action, Adventure, Fantasy, Shounen
Hunters are specialized in a wide variety of fields, ranging from treasure hunting to cooking. They have access to otherwise unavailable funds and information that allow them to pursue their dreams and interests. However, being a hunter is a special privilege, only attained by taking a deadly exam with an extremely low success rate. Gon Freecss, a 12-year-old boy with the hope of finding his missing father, sets out on a quest to take the Hunter Exam. Along the way, he picks up three companions who also aim to take the dangerous test: the revenge-seeking Kurapika, aspiring doctor Leorio Paladiknight, and a mischievous child the same age as Gon, Killua Zoldyck. As the four aspiring hunters embark on a perilous adventure, they fight for their dreams while defying the odds. [Written by MAL Rewrite]
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