The animation seems to overpower an exaggerated plot. Viewers who crave cyberpunk animations consisting of time lapses and vicious fight scenes will have a pleasant taste out of this series. Yet there is much of the plot that may leave the audience hungry. Once you take a bite out of my review, you'll understand what I mean.
~[ S T O R Y ]~ 
Kurozuka focuses on the concept of immortality along with the quest for the meaning of mortality. Initially, I had assumed a vampiric aspect came into play [Kuromitsu sucking blood for example]. As the series progressed, the aspect grew more scientific. Here we have the main character, Kurou, wanting to spend all eternity with Kuromitsu. I once thought it was a romantic struggle between the two protagonists, yet the plot grew more confusing later on. What with the beheading of Kurou to Benkei's murderous motives [due to his desire of having Kuromitsu to himself] to the Resistance against the Red Emperor's Army, just so many subplots made Kurozuka more like a staccato piece than a horror orchestra viewers probably wanted to witness. Even the end itself leaves so much to the imagination that viewers like myself wonder whether the creator intentionally wanted to mess with our minds and trigger heated discussions, or something else we have failed to notice. Other than that, the story could've been portrayed better...
~[A R T]~ 
Post-cyberpunk meets the essence of ancient 12th century art. The serenity of the 12th century atmosphere collaborating with the post-cyberpunk appeal of the anime was rewarded my thumbs up. It brought the animation out more, gluing me to my seat as I endured visual ecstasy. Even the swift fight scenes were brilliant, as expected from the gifted Kurou as well as those involved in battle alongside. Any fan of Death Note can understand that the art between the two animes are strikingly similar. Furthermore, the art was not overexaggerated at all. They were on the dot with their specific time periods, making the anime successfully attractive.
~[S O U N D]~ 
From the miraculous terror of the opening song to the soft tranquility of the ending, Kurozuka had played its music well. The flute and drums matched the ancient liveliness of Japanese culture. The instrumentals had presented the mood well as well as portraying the feel of scenes such as romantic moments, battles, times of agony, despair, hatred, et cetera. I knew what kind of scenes I was expecting from the sound. Nicely done.
~[C H A R A C T E R]~ 
I gave the development of characters a 7 due to the fact that I had expected more from their transformations. Moreover, I expecting a better explanation of the immortality concept. The manga explains more of it whilst the anime has left gaping holes for the viewers' minds to fill. Though Kurou was inconspicuous and monotonous in his expressions, we did have a sense of what he felt inside through his short monologues. I did hope to understand a little more of Kuromitsu, seeing as the series focused more on Kurou's thoughts than anyone else's. Romi Paku and Mamoru Miyano portrayed the voices of their characters well enough for me to give this category a high mark. The rest of the seiyuu's deserve credit. I suppose that the shortness of the series is to blame for cutting short every character's expected developments.
~[ E N J O Y M E N T & O V E R A L L]~ 
Just to be fair, I'll award this anime a 7. Were it to improve in its character and plot development, it would've been awarded a higher grade. Though I do give immense praise to the development of the actual animation. It is different from any other post-cyberpunk anime to exist within the Japanimation realm. The rough grunge scenes, the splash of eccentric hues in the opening and battle scenes, the ancient softness of the 12th century lifestyle - it was all done quite well. Furthermore, the series will leave you thinking on what to value - life or time. Kurozuka is meant to represent the connection between time and life. The two walk hand-in-hand. Without life, there is no time. Without time, there is no life. One affects the other. They both need each other. What is more valuable? Immortality or living to the last minute? That is up to you to decide.