Karin (かりん)

Chibi Vampire, originally released in Japan as Karin (かりん), is a Japanese manga series written and illustrated by Yuna Kagesaki. The story is about an unusual vampire girl, who instead of drinking blood must inject it into others because she produces too much. Chibi Vampire first premiered in the shōnen magazine Monthly Dragon Age in the October 2003 issue, and ran until February 2008. The individual chapters were published by Kadokawa Shoten into fourteen collected volumes.
In 2003, Tohru Kai began writing a series of light novels based on Chibi Vampire, with Kagesaki providing the illustrations. The nine-volume series was published in Japan by Fujimi Shobo. Both the manga and light novel series are licensed for English language release by Tokyopop. Tokyopop renamed the manga series to Chibi Vampire and the novel series to Chibi Vampire: The Novel.
In 2005, an anime adaptation of Chibi Vampire was produced by J.C.Staff and directed by Shinichiro Kimura. Spanning twenty-four episodes, the series aired in Japan on WOWOW from November 3, 2005 through May 11, 2006. It was licensed for an English release to Region 1 DVD, under the name Karin, by Geneon USA. On July 3, 2008, Geneon Entertainment and Funimation Entertainment announced that Funimation had agreed to be the exclusive North American distributor of Geneon titles, including Chibi Vampire. Geneon is still the actual licensor of the series.

# Reference
http://en.wikipedia.org/wiki/Karin_(manga)
Karin: The Complete Series Box Set(Amazon.com)