This is a two episode prequel to the events of Bible Black, which provides the back story of Reika Kitami and Hiroko Takashiro while they were both students at the school, as well as the discovery of Bible Black (the book >_> ).
The main characters for this bout are the aforementioned Kitami and Takashiro (going by Reika and Hiroko), and the new antagonist, Nami Kozono, the class president of the student council.
Basically, Hiroko and her friends are denied a request for a witchcraft club, and shortly they after a member finds Bible Black in an antique shop. They initially cast a spell on a girl named Junko (one of the higher ups in the student council and Nami's lover), and then get a request for a love spell to be cast on Nami. Nami falls for it, and soon, the witchcraft club begins to dominate the school, charging for a variety of spells and such.
Meanwhile, a new transfer has arrived, the virginal Reika Kitami, who's more or less a sweet pure, kind girl with a pure heart, in an amazing contrast to that monster she is in the original series. Reika catches the eye of Nami and constantly rejects her advances, earning Nami's scorn.
I'll let you be the judge of the rest. I think chances are high you're only watching this for one reason only, but if you're one of the few that recognize the plot of Bible Black, you'll enjoy this.
Small little note on the English Dub, several of the voice actresses from the original return, albeit voicing different characters.
