Back when Tokyopop was the manifestation of Kami-sama (at least, in my mind), I saw a bunch of advertisements for an interesting manga called "Mugen Spiral." I finally got around to reading the damn thing only recently.
Story: The premise sounds really good, if you're a fan of "InuYasha" or shoujo. (And there should be A LOT of people who fit that description). Suzuka Yaoyi is a teenager in a long, long, long, LOOOOOOONNNNNNNG line of family mystics. A million demons want her power, so they try to defeat her (but, unfortunately for them, Yaoyi always manages to find the Mew Aqua and blast them halfway across the world). One such demon is Ura, son of the current demon king. Yaoyi kicks his ass and turns him into an adorable black kitten! (Oh yeah, and she seals his powers, too.) Now Ura is stuck following her around like a lost little kit--never mind.
The short version: Hot demon, cool power, hot demon, plothole, mild butt-kicking, hot demon, plothole, hot demon, damsel-in-distress, rage-inducing ending. That's all there is to it. Oh, and cheese. Not the yummy food, but cheesiness. This manga has so much cheese, there should be a nice wine to complement it. (HAHAHA NOT FUNNY.)
The problem with this manga is the ludicrous amount of plotholes (and cheddar, and gouda, and brie, and parmesan...). This manga doesn't wear its shortness well--loose ends are never tied up, romances never developed, and characters are static. And there's cheese. LOTS AND LOTS OF CHEESE.
(Yeah, if you haven't gotten the point yet, this manga is as cheesy as everything Bella Swan says. And because I reminded myself... the dialogue in this manga is bad, even if you don't count the cheese factor.)
Four points for initial interest level. Nah... three-and-a-half.
Art: The only redeeming feature of this disappointment, it is pretty and idealized. Sure, character designs are lackluster, backgrounds are lacking in detail, Ura-as-a-cat looks like a cartoon (STFU 'cause I don't want to hear what you're thinking right about now), and "fight scenes" look awful... but the clothing looks okay! (Though, I will admit: Seeing Ura's fancy-schmancy demon robes next to Yaoyi's school uniform is off-putting.) Also, the art changes pretty drastically around chapter two or three. Weird.
Characters: As aforementioned, static. Plus, they're uninteresting, annoying, cookie-cutter and made with love by the mangaka.
In case you're wondering where the picture is: most of the hits were of pictures from completely different manga and anime ("FMA," "Air Gear," etc.), and I couldn't find any good pictures of all the (very few) characters. Most of the good pictures were of the front cover, which should be on the Anime-Planet page for this manga.
Suzuka Yaoyi: According to the wonderful (RAAAAGE) mangaka, Yaoyi was originally going to be a scaredy-cat crybaby, but was changed into a likable, strong heroine. I dunno... she sure has to be rescued a lot. And at times she goes off-character and becomes a tsundere. At least she has some moments of strength, I guess.
Ura: I think the mangaka intended for him to be quick-witted and punny and sh*t, but all I see is an unfunny, cookie-cutter handsome male character. When he's not rescuing Yaoyi's sorry ass, he's being a weirdo with a father complex (and brother complex, and cousin complex...).
Hakuyo: Perhaps the only likable character in the entire manga, he switches between a slightly-entertaining shota and playing second fiddle. His first shounen-ai-like comment is the only funny moment in the entire manga. Every one of those comments after that is just tired. He doesn't really do anything epic (well, no one does, but who cares) and is mostly just a guy who appears.
Ouga: He had the potential to be a scary, tortured antagonist, but all potential was lost when he took lessons from Uchiha Sasuke and became a mopey emo. What is with this mangaka and father complexes?!
Overall: Is this the worst manga I've ever read? Maybe. (Edit: This statement is terribly inaccurate.) It has numerous plotholes, crappy characters, filler chapters (half the story is filler), an awful ending, and mediocre art. And, above all, enough cheese to make a full-scale model of the Empire State Building. The mangaka's next work should be called this: "To my beloved NicoNicoDesu: F*CK YOU."