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The Character Names: Almost all of the character names are alternate spellings or pronunciations of what would traditionally be evil characters or at least bad boy types. Probably an attempt by the author to go for Evil Is Sexy but it comes off reading like something from bad Fan Fic. A short list follows, but is by no means complete and almost every single example is an insult to creativity. There are other names that are references, but they are not as bad in terms of how unoriginal they are.
Sa Diablo - A surname, shortened to Sadi sometimes. Considering "Diablo" means devil, it's also another example of the author's fixation on demon-related names for the male characters. Also, Jaenelle Angel line.
There is no law against murder. We're told this repeatedly throughout the entire series. There are a couple of empty platitudes about killing leaving a scar on one's soul, but that's not significant enough to make murder a crime (unless of course, it's a member of Jaenelle's court who was killed, in which case your life will be forfeit). As a soul-scarring event, it should be something that would be given much thought, yes? Not appropriate unless all other measures are futile? Then how come Saetan seems to believe it would be okay to snap a girl's bones for attempting to seduce him? Even if he doesn't do it, it's a bit much.
The Dialogue: Either it's Mood Whiplash, pretentious, or just not funny.
World System: The culture, the government, or otherwise how everything is run; it's difficult to imagine how everything doesn't just fall apart on its own. A world like this barely requires Jaenelle. Although it's true somebody has to start the ball rolling, oh well.
The Prose: While it doesn't reach Purple Prose levels it does seem quite pretentious at times. Similar to the dialogue.
Count how many times Jaenelle will speak in "a midnight voice" or a "midnight whisper". Or when her tone will become "sepulchral". Alternately, the "soft thunder" in Saetan's voice, or when either he or Daemon speak "too softly". For added fun, try the "bored, sleepy look" either male gets that the author tries to pass off as being intimidating. Finally, all the hissing and snarling that goes on when anyone's angry.
The Relationship: Daemon is creepily obsessed with Witch. His desire to "mate" with her is brought up at every opportunity, as are his assertions that he was born to be her lover. It's played as love, devotion, or maybe even destiny, but when you consider the fact that he's hunting down a woman who may not know of his existence (and isn't even a woman yet in the first book!) explicitly to seduce her, it's disturbing.
Jaenelle has many, many friends. They're all supposed to be high-ranking Blood such as Queens and Warlord Princes. Two of them are even triple-gifted like her and there's hinting of a power triangle between them. Sadly, none of these friends, not even those two, are given much development. Many are no more than names. The only purpose they serve in the end is to show how loved by all Jaenelle is.
Jaenelle Angelline is beloved by all but the most evil and corrupted souls. To put it bluntly, if you don't like her in the series, the problem is with you, not her. You are fatally flawed in some way if you cannot see Jaenelle for the shining beacon of hope she is. All men are attracted to her (save Lucivar, who sees her as a little sister), and in the case of the nastier types, this translates as a desire to rape her.
Very true. See the difference between what happens to Theran Greyhaven and his cousin, Jared Blaed. Theran doesn't see her as THE QUEEN and he suffers lots of humiliation. Jared recognizes her right away and, well, he gets everything he wants.
Then there's her powers. Not only does she have one of every color of Jewel "to practice with", she has thirteen uncut Black Jewels, all of which are gifted to her by Lorn, Prince of the Dragons, the closest thing you have to God besides Jaenelle herself. These Jewels later become Ebony Jewels, which are said to be "darker than Black". Jaenelle is stated to be somewhere along the lines of six thousand times stronger than Daemon and Saetan combined, and can easily wipe the Blood out of existence due to having the non-flaw of being "too strong". The author "corrects" this by having her powers nearly kill her at every opportunity, to the point that, much like the rapes in these books, it doesn't matter that Jaenelle's organs are failing again.
Possibly a rare case where her being a total God-Mode Sue is justified. Jaenelle is made of everyone's dreams about what the ideal Queen is. She was made out of centuries worth of people's Mary Sue fantasies.