Is Tennis no Oujisama: Mini Theater hentai?
English title: The Prince of Tennis: Mini Theater
No
Rated PG-13 (Teens 13 or older) on MyAnimeList and not tagged as Hentai.

Special · 2009 · 3 episodes · PG-13 - Teens 13 or older
Comedy, Shounen
Mini Theater 1 Seishun Academy faces off against Rikkai University-Affiliated Middle School in an unofficial rematch. Instead of playing tennis, the players end up getting distracted by a game of Acchi Muite Poi and a battle between whose data is superior. Mini Theater 2 Mysterious love letters are appearing in shoe lockers at Seishun Academy. Sadaharu Inui sees this as a perfect opportunity to observe the regulars' response to receiving a love letter addressed to them. Mini Theater 3 Seiichi Yukimura asks his vice captain, Genichirou Sanada, to be the model for his next painting. Unfortunately, Sanada's reluctance doesn't seem to be doing anything for Yukimura's creativity. [Written by MAL Rewrite]
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