There really is no coherent, sequential story to speak of. It starts out intresting enough with Takumi, a reclusive otaku and a few creepy incidences/people randomly popping into his life. The creepy, mysterious stuff would be GREAT...if it were explained at all; but instead of explaining anything that's happening to this kid, more strange girls just keep showing up in his life out of nowhere and he keeps talking to this creepy 'Shogun' guy online (has he never heard of the 'block user' option?). To top that off, he somehow seems to suffer from random amnesia not caused by anything at all, and randomly forgets who his best friend is and thinks she's evil. Why? We never quite find out. Then, said best friend and that bunch of random girls I told you about somehow get these ginormous illusionary swords and Sena tells Takumi that (from what I could gather) everything he knew was a dillusion and these people called Gigalomaniacs (again, something thats never explained) could control dillusions and unbeknownced to him, he's a Gigalomamiac. Then you find out that there's apparently some evil organization (that again, came from nowhere) and they wanted to destroy the world. Apparently this is supposed to have some connection to Shogun and the murders, but if there is anything connecting it, it's not made very clear at all. To top that all off there's a weird formula that's supposed to destroy the world or something and the phrase "Who's eyes are those eyes?" shows up EVERYWHERE without any real rhyme or reason that we know of, all we know is that everytime Takumi hears that phrase...he randinly throws a fit for no apparent reason. Basically, there really is no understandable story in this anime, it's just a bunch of supposedly "connected" (not really) events thrown together into this garbage that makes just about as much sense as my fish jumping out of his tank and driving a monster truck around my house. Really, if my fish did that, I'd be asking alot of questions, just like I was at the conclusion of this anime.
This was perhaps this shows only saving grace, is that the animation looked phenominal. Personally I liked Ayase's gothic style outfit in the fact that it was probably the most orginal outfit in the entire show, next to Seira's, but I personally think Ayase's had much more effort put into it. Since the outfits rarely differed (my reasoning for 1pt off) from character to character, the hairstyles differened a little more and were drawn very nicely and helped to identify the characters since we know very little else about them. Another aspect of the art that also looked great was the Di-Swords, I have to admit those looked really awesome and each was significantly different from the others. They also weren't you're average anime swords, they were shaped differently, coloed extremely differently and most of them had areas that glowed which looked really cool.
The opening theme was fairly forgetable, while it did go sort of well with the series, it just wasn't that great and the voice was really sort of obnoxious towards the end as it sounded like the singer continued to stay with the same note eventhough it was too high for her; and that's what you were left with just before every episode started. The seiyuu's all served there purpose pretty well, they didn't really add to the characters, they didn't take away from them, but they did match the character pretty well...except for Sena, Yua (while she was confronting Takumi) and to some extent Ayase as they were all fairly monotoned at certain alot of points (Sena nearly all the time) and at those same points the voices were oddly deep to the point where it just sounded weird. I mean their Japanese teenage girls for crying out loud. The closing was decent and catchy as the song itself...but as a closing for this particular show, it really didn't fit very well. Nor did the lyrics really make a whole lot of sense, so maybe the lack of making-sense is the connection? Thats really the only way the show and the closing could go together at all.
Very many of the characters were either not developed at all, or their development was very confusing. The worst explained characters probably being Shogun and Takumi...who were supposedly each other in the first place somehow but Takumi didn't really know that Shogun was actually him and that he himself was fake. Weird right? confusing right? Exactly, they really explained none of that at the ending moments in the show, you just sort of find out that Shogun is apparetly Takumi and you never really find out how that is. We know Nanami is Takumi's kid sister and thats all we know about her. We know Rimi is supposed to be Takumi's best friend but he forgets that and thinks she's evil. Why? We don't know, it never tells us anything else about Rimi or her relationship with Takumi. Kozue (or Kozupii) somehow has telepathic abillities that we, again, know nothing about. Why does she have them? How did she get them? We don't know any of it. The only two characters that we actually know a bit about are Ayase and Sena; Ayase is a very famous rockstar as well as a student at the same school as EVERY OTHER CHARACTER (how does that work out?) and is also shown to be pretty intellegent. Probably one of the most boring characters, but also the one we know the most about is Sena; she is a very cold character who's obsessed with killing her hobo father because when he was a big-wig scientist he sacreficed her mother and little sister for an experament and she never forgave him. Other than what I just told you about, we really don't know much more about any of the characters.
Basically this show is complete garbage that doesn't make any sense. It's like a random pile of garbage dumped on someones head and they were walking around with it not even knowing it was there; it makes absolutely NO sense what so ever and NOTHING is ever explained to you. So if you asked the person why the garbage is on their head and they didn't explain to you why its there, thats exactly like Choas;Head, even for anime nothing makes any sense, and not in a funny way either, it makes no sense in an annoying way becuz you have no clue what's going on. My advice to you, unless you've played the game, stear clear of this anime.