Is Nodame Cantabile: Finale - Mine to Kiyora no Saikai hentai?
No
Rated PG-13 (Teens 13 or older) on MyAnimeList and not tagged as Hentai.

Special · 2010 · 1 episodes · PG-13 - Teens 13 or older
Adult Cast, Comedy, Josei, Music, Performing Arts, Romance
Violinist Kiyora Miki meets with Shinichi Chiaki, Megumi "Nodame" Noda, and their two friends to visit world-class conductor Franz von Stresemann; upon arriving at his residence in Vienna, they discover that the maestro has escaped to Japan. As they make the most of their wasted trip by visiting important landmarks in the historical capital of classical music, Kiyora has a confession to make: she has not seen her boyfriend Ryuutarou Mine for an entire year and is still busy preparing for an international competition in Paris. Chiaki and Nodame promise to attend the final round, but when the two are back in Paris, they receive an unexpected guest... [Written by MAL Rewrite]
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