The new anime Itsuka Tenma no Kuro-Usagi has a very generic theme, but a unique story. It takes place in a city, and starts off in a high school. The main character, Taito was poisoned by a vampire at a very young age and had forgotten about it for 9 years until he started to have dreams about the girl in his childhood during class and flash backs at random times. Having forgotten memories of the vampire Himea, her existence in the world was gone and she became trapped in another dimension. I'm unsure how he forgot about her, but I think it's related to someone else similar to Taito. The first episode is quite entertaining, unparalleled in its colors, and keeps you on the hook for the next episode.
So, you better watch it or else!