Is Isshuukan Friends. Tomodachi to no Omoide hentai?
No
Rated PG-13 (Teens 13 or older) on MyAnimeList and not tagged as Hentai.

Special · 2014 · 1 episodes · PG-13 - Teens 13 or older
Drama, School, Shounen
Recap episode voiced over by Kaori and Saki, who talk about the developments in the show. Included in the 5th volume of the Blu-ray/DVD releases.
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