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

TV · 2014 · 12 episodes · PG-13 - Teens 13 or older
Adult Cast, Comedy, Crossdressing, Josei, Parody
Kou comes to a slum neighborhood in search of his elder brother Takumi and finds him to have become the head of a private detective firm. Kou is drafted by Takumi to do errands and chores in the detective firm, and they come to meet various interesting people... (Source: MAL News)
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