True Blood, Season 1

Bill:
[after Malcolm and his gang have left] I'm sorry you had to witness that. Your visit was unexpected.

Sookie:
What's Hep-D?

Bill:
Hepatitis D is the only blood born pathogen to which we are susceptible. Malcolm must be furious.

Sookie:
Hepatitis?

Bill:
A mutation. Relatively harmless to humans, oddly enough.

Sookie:
I've never even heard of it.

Bill:
That's because we've kept it out of the media.

Sookie:
And it makes you sick for a year?

Bill:
No. It just makes us weak for about a month or so. The biggest danger to us from Hep-D is being captured and staked during that time.

Sookie:
Yeah. You don't want your weaknesses to be public knowledge.

Bill:
Precisely.

Sookie:
And what the hell did you mean, "Sookie is mine"?

Bill:
I was communicating to the others that you are my human and therefore I was the only one who can feed on you.

Sookie:
You most certainly cannot feed on me!

Bill:
Well of course I can't, Sookie. But had they known that, they'd've considered you fair game and I wouldn't have been able to stop them from attacking you. It would be three against one, and Malcolm is much older than I am and quite strong.

Sookie:
And... you and Diane dated?

Bill:
We had sex once, just after she was made vampire back in the late 1930's.

Sookie:
What? Gross. Bill, she's so... they-they're all so mean, so ...

Bill:
Evil. Yes, they are. They share a nest and when vampires live in nests, they become more cruel, more ... vicious. They become laws unto themselves. Whereas vampires such as I, who live alone, are much more likely to hang on to some semblance of our former humanity.