Is Nazo no Kanojo X hentai?
English title: Mysterious Girlfriend X
No
Rated PG-13 (Teens 13 or older) on MyAnimeList and not tagged as Hentai.

TV · 2012 · 13 episodes · PG-13 - Teens 13 or older
Romance, School, Seinen
First encounters are always memorable because regardless of the outcome, new experiences are sure to happen. For Akira Tsubaki, a young boy who knows next to nothing about girls, and new transfer student Mikoto Urabe, a mysterious girl who wears a cold facade, their first encounter takes a turn for the romantic. Through a series of strange events, Tsubaki suddenly falls in love with Urabe, and together they develop a curious bond. Thus begins the romance and mystery of Urabe, a girl who seems to have a unique way of expressing her emotions. [Written by MAL Rewrite]
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