The May issue of Shonen Ace magazine is announcing that CLAMP will collaborate with Production IG on a new Blood original series called Blood-C, which will air this July.
According to ANN, CLAMP will be responsible for providing not only the original design concepts, but also the story.

Quoting ANN:
In addition, Ranmaru Kotone (Diasta of Ultima Thule, Toki wo Kakeru Shoujo -Tokikake-) will adapt the project into a manga, which will launch in the July issue of Shōnen Ace. The official website for the project will open at the www.blood-c.jp address.
Two weeks ago CLAMP were eating pizza with Production IG’s staff, they were probably discussing about the project =)
I wonder if the C in the Blood-C title stands for “CLAMP”?
What caught my attention was the fact that CLAMP is not only providing the character design, but also the story, which makes this project the first original anime series by CLAMP. This is the first time they create the story for an original anime series. I wonder if Ohkawa will actually write some scripts or just provide the main plot…
I’m very excited about this! Yay for CLAMP exploring new territories =)
Stay tuned for more news!