In the book:
The coven that moves into Shreveport is headed by a very nasty witch/were named Marnie. She's a witch, a werewolf, and a regular drinker of vampire blood, so she is freakishly strong and very powerful. She wants to take over Shreveport's supernatural assets and wealth, so she sends her coven members out to threaten Fangtasia and force Eric into handing the business and profits over to her. He refuses and she casts a spell on him that wipes out his memory.
Sookie finds him running down the road to her house with no clue as to who he is. She takes him in and agrees to hide/care for him until the vampires can track down Marnie and her coven and force them to release Eric from the spell. Marnie has put out missing person posters and is making all sorts of efforts to find Eric, so there is a considerable amount of danger for Sookie in dong this.
In the book, Sookie and Eric suddenly wind up spending a lot of time together. Time in which Eric is no longer the ambitious head vampire, but is now very open and honest. And of course, what else do you do when you have lots of free time with a sexy vampire? They end up in bed together pretty damn quick. Except all that bed stuff starts out in the shower. Let's just say it is very steamy.
So viewer expectations are pretty high amongst those who read the books!
Hope that helps a bit?
You'd probably enjoy reading the book - it's the fourth one called "Dead to the World".