Blood Alone(2005)

BLOOD ALONE

Witness the touching relationship between young vampiress Misaki and her human companion, the former vampire hunter turned investigative author, Kurose Kuroe, whom she'd die to protect. For recently turned vampire Minato Misaki, vampirism and the beastly powers that come with it are something that she wouldn't wish upon her worst enemy, let alone her beloved Kuroe. But Kuroe's supernatural investigations make him a regular target of not only vampires but of all sorts of undead creatures of the night. The only way to save him from these deadly threats may be to do the one thing that Misaki fears the most: to turn Kuroe into a vampire for his own protection

(Source: Seven Seas Entertainment) It was originally released as doujinshi publication, later serialized in ASCII Media Works's Monthly Comic Dengeki Daioh magazine from the April 2004 issue to the April 2010 issue. After a short pause, the serialization resumed in Kodansha's Evening magazine from issue 24 in 2010, but in issue 5 of 2014, the editorial department announced its abrupt conclusion. After that, three additional volumes concluding the story were published again in doujinshi form by the author in both physical and digital form.