Mitsugu Banba is a high school girl who finds meaning in donating blood. She frequently visits a blood bank to donate blood, despite being harshly treated by the nurse. One day, she encounters a beautiful girl who looks like she's from overseas at the blood bank. The pale girl looks like she's about to faint any minute, but then, she starts destroying the blood bank. The girl loses consciousness and Mitsugu takes her home... (Source: Official Website)

Once, vampires and humans lived in harmony. Now, a young girl and a vampire queen will search for that Paradise once again. In the divided world of the future, two girls want to do the forbidden: the human wants to play the violin, and the vampire wants to see a wider world.

In the town of Kurouzu-cho, Kirie Goshima lives a fairly normal life with her family. As she walks to the train station one day to meet her boyfriend, Shuuichi Saito, she sees his father staring at a snail shell in an alley. Thinking nothing of it, she mentions the incident to Shuuichi, who says that his father has been acting weird lately. Shuuichi reveals his rising desire to leave the town with Kirie, saying that the town is infected with spirals. But his father's obsession with the shape soon proves deadly, beginning a chain of horrific and unexplainable events that causes the residents of Kurouzu-cho to spiral into madness.

During the summer holidays, energetic Hana Uzaki spent most of her time accompanying her lonesome upperclassman, Shinichi Sakurai. Now that school has resumed, Uzaki's teasing continues to ramp up, much to Sakurai's constant annoyance. Nevertheless, no amount of ridicule can damage the pair's relationship—which only seems to be getting better as their college days fly by!