Is Maria†Holic Alive hentai?
No
Rated PG-13 (Teens 13 or older) on MyAnimeList and not tagged as Hentai.

TV · 2011 · 12 episodes · PG-13 - Teens 13 or older
Comedy, Crossdressing, Girls Love, Parody, School, Seinen
When Kanako Miyamae transferred to a new all-girls school, she hoped to find true love. What she found instead was the beautiful Mariya Shidou, a charming classmate Kanako met on her first day. But Mariya has one flaw: she is actually a cross-dressing boy! After discovering Mariya's secret and becoming stuck with him as her roommate, Kanako's life has become a series of misfortunes. All she wants is to find the girl of her dreams, which is hard to do with the meddling of the sadistic Mariya and his sharp-tongued maid Matsurika Shinouji. Maria†Holic Alive continues the story of Kanako as she deals with being Mariya's roommate and aims to find true love, while enduring high school itself. [Written by MAL Rewrite]
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