Karin-cute, cheerful high school student. She loves the sun, prepares with garlic and work part-time waitress. In general, it is quite normal ... with the exception of one. Karin Vampire and lives with his parents and two brothers and sisters, which are also vampires. But even among them she is different, because it does not take blood, but gives blood that increases in her body. Once a month, Karin accumulates blood, and if you do not remove it quickly, it will have a lot of blood from the nose (serious bleeding from the nose). And once at school, he meets Kent Usui, and he appears a feeling of bleeding from the nose in the first place. It seems that Karin never had a "right way to" solve its problems.