Maryann knows the second she takes the knife from Eggs's hands, on his knees: She can feel it. Her body responds, she weeps and writhes: This is the vessel after all. Sam calls out silently to Sookie and she runs to him, putting hands on his shoulders, as he weakens. "I'm sorry. I'm so, so sorry..." He fights to see her, and thinks a single thought: Destroy it. All of it. She nods, and runs to the tree while Bill makes his escape. First, the egg. She smashes it on the ground. "You killed our sacred egg!" shouts clueless Tara, who's barely been following any of this. "It's not sacred. None of it's sacred!" Sookie shots, tossing her garland aside. "It's evil!" she yells, shoving the goddess over with that fire in her hands.
Maryann is mortified; her shame turns to rage as fast as Sarah's passion. "How dare you spoil my offering? Lord Dionysus, forgive me?" She turns to the crowd, Sam's blood smudged down her throat, changing gears like the Newlins, looking for a better recipe. "Allow me to sacrifice all of them for You," she says, vibrating until the crowd is on their knees, screaming in pain as she dances. Sookie holds Tara up, shouting at Maryann even as she realizes this won't cut it either. She changes gears again. "You brought this upon everyone!" Maryann howls in that dumb scary voice she gets, and plunges her hands into the earth, coming up with poison claws. Sookie runs through the forest from her once again, calling for Bill: The claws, the fear, the blood beating in her heart, under the moon just like this. She falls, overcome, and Maryann raises fists to strike.
A bellow rings out across the road, in the darkness. A perfect white bull, without blemish, in the moonlight.
Rough music itself, of which the shivaree is a subset, goes back to the 1700's: Somebody who has violated the standards of the community is scapegoated, and they bring the pots and pans to his or her house, keep her up all night, rattling bones and cleavers, blowing bull's horns. It's extreme social sanction, in this form; like any scapegoating ceremony, it's an acknowledgement of the wrongdoer's place in the community as much as it is about her behavior.
It's not a shunning, or banishment: It's the opposite. Any time Dionysus comes to visit, that's rough music: It's never about making it go away, it's never about killing the little black-eyed girl. It's about celebrating her. Giving her a little time, a little slice of night, before she goes away again. If we are all the same amount of dirty, there is no shame, because we are all the same amount of clean.