Is Gi(a)rlish Number hentai?
English title: Girlish Number
No
Rated PG-13 (Teens 13 or older) on MyAnimeList and not tagged as Hentai.

TV · 2016 · 12 episodes · PG-13 - Teens 13 or older
Adult Cast, Showbiz, Slice of Life
College student Chitose Karasuma is determined not to do boring things as she enters the adult world. To this end, this bad-mannered beauty barges into a facility that trains would-be voice actors and actresses, somehow landing a job at "Number One Produce," a seiyuu agency managed by her older brother, Gojou. In Chitose's mind, she's poised for greatness, but finds herself at a loss when she continues to only get minor roles. As she clashes with other girls in the agency, including a cunning airhead and a girl with a Kansai accent, Chitose is about to learn that there's more to succeeding in this competitive industry than she imagined. (Source: ANN)
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