Is Dance in the Vampire Bund: Special Edition hentai?
No
Rated R (17+ (violence & profanity)) on MyAnimeList and not tagged as Hentai.

TV Special · 2010 · 1 episodes · R - 17+ (violence & profanity)
Action, Supernatural, Vampire
A Dance in the Vampire Bund recap episode featuring re-edited footage from the first 7 episodes.
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