He's My Only Vampire 

You are my “thrall”–mine and mine alone… When Kana, a student at St. Agatha Academy, lays eyes on her long-lost childhood friend Aki amid the throng of the metropolis, the gears of destiny begin to turn! Meeting with an unfortunate accident not long after, Kana finds herself pulled from the arms of death by a vampire–Aki. Now Kana must give herself over to Aki, body and soul, as his “thrall,” and soon she is trust into a dangerous game to obtain demonic powers known as “STIGMA,” which could very well spell the end for her all over again!