Overall Rating: A+
Synopsis: Ichigo Kurosaki sees ghosts, and fights...a lot. All of this is pretty normal for Ichigo, but then he meets Rukia Kuchiki, a Shinigami (Death God) and member of the mysterious Soul Society. When a Hollow, an evil spirit, attacks Ichigo and his family, Rukia attempts to defeat the Hollow, but is wounded. To help him save his family, she lends Ichigo some of her powers, but something goes wrong, and Ichigo absorbs every last drop of her energy. Ichigo becomes a temporary Shinigami, and works with Rukia to handle the hunting of hollows until Rukia can recover. At least, that was the plan...
Before I picked up the manga, I saw the first four episodes of the anime at Stellarcon '06. It was a fansub (this was before it was airing on Adult Swim), so the translation wasn't great, but I fell in love with the characters and mythology of the series. I immediately started picking up the manga and planning a costume for Ichigo. A few months later, I cosplayed Ichigo at Heroescon, had read all of the manga that had been translated, and watched as much of the anime as I could get my hands on.
So, what's the big deal, right? I think it comes down to the characters. There are dozens of of them, and the writer Tite Kubo takes the time to give them all detailed backgrounds and relationships. I'm 19 volumes in, and while there's plenty of action, it's the character development I'm hooked to.
In the first 19 volumes, there are three main groups of characters, humans, the Shingami, and the Quincies. When humans die, their souls become Wholes or Hollows. Wholes are normal spirits, but the spirits that become Hollows are corrupted souls that must feed on the souls of the living (kind of like spiritual vampires). The Shinigami release Wholes and help them cross over to the Soul Society (the spirit world), and cleanse the Hollows so that they can cross over as well. They do so using big ass swords called zanpakutō.
The Quincies use bows made of spiritual energy in the form of bows to hunt Hollows, similarly to the Shinigami. However, unlike the Shingami, who purify the souls of the Hollows preserving the balance of souls between the two world, the Quincies destroy them. This endangers the balance of the world, and as a result the two groups went to war. The Shinigami won, and there is now only one Quincy left, Uryū Ishida. Despite his hatred of Shinigami, Uryū eventually becomes friends Ichigo, and even travels to the Soul Society with him.
This only scratches at the surface of the series. I have only seen ~50 episodes of the anime, but what I have seen follows the manga very closely. I highly recommend checking out the series, it's fun, interesting, and has some great cosplay opportunities.