In the world of niche anime, "exclusive" usually refers to the or Blu-ray (BD) specials in Japan. These versions are the definitive way to experience the creator’s original vision. For Isekai Harem Monogatari , the exclusivity lies in the balance between the "Ecchi" elements and the actual progression of the fantasy plot.
Heroine Tsubaki – Bond Established (Exclusive). Attribute gained: Spiritual Sanctuary. isekai harem monogatari exclusive
Here's a brief overview: