Is Sayonara Zetsubou Sensei Jo: Zetsubou Shoujo Senshuu hentai?
No
Rated PG-13 (Teens 13 or older) on MyAnimeList and not tagged as Hentai.

Special · 2008 · 1 episodes · PG-13 - Teens 13 or older
Comedy, Gag Humor, Parody, School, Shounen
A special summary episode of the first season of Sayonara Zetsubou Sensei, focusing on seven of the girls: Komori Kiri, Matoi Tsunetsuki, Kobushi Abiru, Kimura Kaere, Kitsu Chiri, Sekiuchi "Maria" Tarou and Hitou Nami. Note: This entry also includes the 24 minute version which aired on BS11.
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