This is a set of 4 specials that consist of side stories bridging the gap between the first and second series, so they will center around Hei, Yin and what happened to them during that time until Ryuusei no Gemini.
These are direct download links.
Episode 1
[sub] - 1080p - .mkv - 134 mb - [?] - Megauload
[sub] - 720p - .mkv - 335 mb - [JewInc] - Megaupload Part 1 | Megaupload Part 2 | Megaupload Part 3 | Megaupload Part 4
[dual audio] - 720p - .mkv - 342 mb - [CBM] - Megaupload
Episode 2
[sub] - 720p - .mkv - 314 mb - [BSS] - Megaupload
[dual audio] - 720p - .mkv - 319 mb - [CBM] - Megaupload
Episode 3
[sub] - 720p - .mkv - 391 mb - [BSS] - Megaupload
[dual audio] - 720p - .mkv - 478 mb - [CBM] - Megaupload
Episode 4
[sub] - 720p - .mkv - 303 mb - [BSS] - Megaupload
[sub] - 720p - .mkv - 303 mb - [BSS] - Megaupload
[dual audio] - 720p - .mkv - 391 mb - [CBM] - Megaupload