Is Machine-Doll wa Kizutsukanai Specials hentai?
English title: Unbreakable Machine-Doll Special
No
Rated R+ (Mild Nudity) on MyAnimeList and not tagged as Hentai.

Special · 2013 · 6 episodes · R+ - Mild Nudity
Action, Ecchi, Fantasy, School
Original animation to be included in the BD and DVD volume releases of Machine-Doll wa Kizutsukanai. Volume 1: "Soshite Futari wa Manabisha e (And So They Arrive at School)" Volume 2: "Irori, Rotenburo de Sosou suru (Irori Has an Accident at the Open-Air Bath)" Volume 3: "Char and Frey, Senritsu no Bathroom (Charl, Frey, and the Bathroom of Terror)" Volume 4: "Akabane Nadeshiko, Natsu no Yo no Yume (Nadeshiko Akabane, Midsummer Night's Dream)" Volume 5: "Kojin Jugyou: Imishitsu de Bijo Futari to~ (Private Lesson - Two Beauties in an Infirmary)" Volume 6: "Bishoujo Shuugou! Mizugi Darake no Daisoudou (Pretty Girls Gather! Swimsuit-Stubbed Pandemonium)"
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