This should've just been named "Fushigi Yuugi Redux" or something, because that's essentially what it is; it's a watered-down version of Fushigi Yuugi with fewer bishies, ultra typical shoujo art that can at best be called decent, and instead of friends playing opposing mikos, this time it's a pair of twin sisters. Yume discovers she's a miko and is supported by the Seiryuu/Byakko/Genbu of the upper world and the Suzaku of the underworld on her quest to restore order to both worlds by finding the runaway unicorn. Yes, I'm serious.
Aside from being an essential rehash of familiar stories, all the "character development" (if you can call it that) and relationship-building takes place within the first 4 chapters or so, at a breakneck speed. If you think you can at least get a cute, well-developed romance from this, you'll be disappointed.
Rekka (the underworld Suzaku) gets to know Yume in the first 2 chapters when she discovers her powers, and by chapter 4 we're already getting raging jealousy from all members of the love square, forced kisses and so on. By the end of the first volume, they're already deeply in love and ready to die for each other. I mean... wha?
What makes this even more tiresome is the fact the whole main conflict happens precisely because one member of the love square didn't take rejection well and went off the deep end. I kept praying that someone would just slap a bit of sense into the crazy party, but then I suppose we wouldn't have a manga that stretched over 3 volumes.
This manga is bland, pedestrian, banal, insipid, hackneyed... you get the idea. The only reason why I scored it higher than a 3-4 is because of the decent art and the reasonable ending. Don't bother wasting your time reading this.