Laws of Motion

A/N: I thought of this story while answering a Physics exam, which I probably failed.

***

Laws of Motion

***

Inertia

Andromeda bites her lip and leans over to peer at her younger cousin intently. Wisps of black hair flying and cheeks red from the cold, Sirius sits on the stool and eagerly plunks the Sorting Hat onto his head. Andromeda knows what's coming--has known it ever since Sirius sprayed distilled dragon's blood on the family tapestry at age three and was spanked thoroughly for it by his father.

"Slytherin, Slytherin, Slytherin," Bellatrix whispers beside Andromeda.

"GRYFFINDOR!"

Later, Bellatrix corners Sirius and tells him that he's a disgrace to the family name, to Toujours pur. Even from a distance, Andromeda can see Bellatrix mouth the words "family tree" and "Imperius." Andromeda reaches them just as Bellatrix sweeps off to the Slytherin common room, black hair and black cloak trailing behind her. One of Andromeda's fellow prefects--Tonks, was it?--is yelling at Bellatrix's retreating back to leave people who haven't done anything to her alone. By a stairwell, Sirius is putting on an admirable show of bravery, but Andromeda can still see him for what he is--a wide-eyed eleven-year-old toeing the line between family loyalty and self-discovery without even realizing it.

"Andy," Sirius says, burrowing his head in her hair as she crouches down and embraces him. "What is her problem?"

"She just doesn't like it when things she doesn't want to happen still happen," Andromeda says soothingly. "I think she got a little carried away," she adds as an afterthought, as if everybody who felt what Bellatrix is feeling threatens to use an Unforgivable Curse on their prepubescent cousin.

"She's barking mad," Tonks mutters, still standing nearby. Andromeda looks up to him, unsure whether to glower at him or agree. But before she can reach an internal compromise, Tonks seems to realize that he has insulted Bellatrix Black in front of one of the two people who love her the most. He shifts uncomfortably. "I suppose you've got everything under control here?"

"Yes," she says coolly. Bellatrix is not mad.

"I'll see you around, then," Tonks tells Sirius, giving him an elder-brotherly pat on the back.

"Bye, Ted," Sirius replies a little more cheerfully.

Tonks gives Andromeda a polite nod and walks down the same corridor that her sister angrily stormed through a few moments ago. It only occurs to Andromeda now that Tonks is really tall, and that in their first conversation outside Potions, he had already put into words what she has always been scared to think.

***

"No grade below Outstanding in her OWLs," Cygnus Black tells Abraxas Malfoy proudly. "And she's a Prefect."

"And she's beautiful," observes Abraxas, leering at Andromeda. He turns to her father. "She is still a--?"

"Of course," Cygnus cuts in. "She is everything that a young pureblood woman is expected to be."

Of course I am, Andromeda thinks sourly. Narcissa tugs at Andromeda's dress from behind as Lucius Malfoy makes his way towards his father.

"Mr. Black," Lucius says, bowing. He turns to Andromeda. She feels Narcissa's grip on her dress disappear as her younger sister scampers off--to talk to Bellatrix, no doubt. "Miss Black," Lucius says, planting a chaste kiss on Andromeda's hand.

"You have met my son Lucius before, haven't you?" Abraxas asks Cygnus.

"Yes, yes, of course," Cygnus says, regarding the younger Malfoy with keen interest. "Out of Hogwarts already, am I right?"

"Yes, sir," Lucius replies politely. "Taking care of the family business."

"Has a better head for money than the Gringotts goblins themselves," Abraxas adds.

"No doubt," Cygnus agrees, for reasons Andromeda doesn't know.

"And you, Andromeda," Abraxas says, turning his unsettling blue-grey gaze back towards her, "what do you plan to do after Hogwarts?"

Andromeda has never really thought that anyone would ask her that before and actually listen to her answer. Then again, Abraxas Malfoy could be asking just to see whether she is willing to do nothing for the rest of her life, as a young pureblood lady ought to do.

"I'm thinking of becoming a Curse Breaker," she says shyly.

"What?" Lucius says, all politeness replaced by disbelief.

"Why?" Abraxas asks.

"Yes, Andromeda, why?" Cygnus adds, his voice a curious mixture of contempt at the thought of work and affection for his most diligent daughter.

Andromeda wants to say that it sounds like the most exciting thing in the world. That she wants to travel to far away places in the pursuit of knowledge and adventure, while at the same time helping her fellow wizards by safeguarding their wealth. That she finds the idea of living out of a trunk strangely appealing. In short, Andromeda wants to tell her father, her likely fiancé, and her almost-certain-future father-in-law everything that Ted Tonks told her in their second conversation outside of class, when they were both on their way to Professor Slughorn to ask him whether they still needed to read on the history of Amortentia again.

***

A glittering green skull, with a snake jutting out of the mouth, is hovering over Hogsmeade.

Andromeda instinctively searches for her fellow schoolmates. She rounds up a few random Ravenclaw third years on High Street and herds them to the Hogwarts gates. Once they are safely in the grounds, she returns to the places in Hogsmeade that are popular with the students. To her immense relief, Fabian Prewett and Emmeline Meadowes are already casting temporary Shield Charms on the students milling in Honeydukes and leading them back to the school.

"Andy, go to Zonko's!" Emmeline says shrilly as the shop next to Honeydukes is set alight.

Like an Inferius, Andromeda automatically obeys. She speeds down the hill towards the popular joke shop, gathering a group of crying Hufflepuff girls and a panicky group of Gryffindors and casting a Shield Charm on them. Andromeda detachedly notices the flames erupting on either side of her and her group, the lack of Slytherins in the vicinity, and the hooded figures appearing briefly between the buildings and trees, which she may be just imagining anyway. The ominous-looking green skull looms ahead of her on the path; it seems to be drifting closer to Hogwarts, or maybe that's just late afternoon sunlight playing tricks...

"Shut up and go straight to your common rooms!" Andromeda shouts at one of the sobbing Hufflepuff girls as they reach the gates. "Don't stop until you get--"

Andromeda hears a thunderous crash coming from behind her. Without finishing her sentence, she runs back to the village--down the hill--her heart and brain and a stitch in her side all throbbing painfully, Andromeda sprints towards the direction of Madame Puddifoot's, where most of the noise seems to be coming from--

She nearly trips over a pair of legs lying motionless on the path. Seeing the blood stains on the jeans and fearing the worst, Andromeda looks to see whether the legs are still connected to an intact body. The body is Ted Tonks's, and he is being futilely dragged away by the skinnier Edgar Bones.

"Got Stunned or something," Edgar manages to gasp. "I don't know, he may have even been concussed ... I've been with him ten minutes and he hasn't moved..."

"Not ... dead?" Andromeda chokes out, dropping down on her knees to inspect Tonks's wounds.

"Don't do that out in the open!" Edgar swats her hands away from Tonks's scarred cheeks. "They might find us! Quick, help me bring him over to that bush over there ... My wand snapped, have you got yours?"

Andromeda levitates Tonks's body a few inches above the ground and brings him to a secluded spot behind a giant oak tree.

"We can't move him anymore," Andromeda whispers, gingerly prodding at Tonks's arms and legs with her fingers. "I think he broke something." She looks up to see Edgar crawling out of their hiding place. "What do you think you're doing?!"

"I have to find Amelia," he explains hastily. "Take care of Ted. Oh look, I think he's waking up... "

"You haven't got a wand!" Andromeda hisses warningly, but Edgar ignores her and runs off to look for his sister.

"Black?"

Tonks's eyes slowly flutter open. Looking down into them, Andromeda gets the strange feeling that he isn't seeing her clearly.

"Tonks," she breathed, slumping against the tree. She could feel her heart beating wildly in her ribcage and the vein in her temple pulsing faster, but thank Merlin, she thinks, not really knowing why, thank Merlin that Ted is alive.

"Let's get out of here," Tonks says. He tries to sit up but collapses. "Ouch ..."

"You've broken a couple of bones," she tells him. "I'm going to levitate you instead." She pulls out her wand from her pocket and is about to swish and flick when she hears a familiar voice.

"Andromeda Black, what are you doing?"

Andromeda turns around to face Bellatrix--composed, unscathed Bellatrix.

"Bella!" She knows she should be tending to Tonks, but Andromeda hasn't seen her sister since the annual Black Christmas ball four months ago. She leaps into Bellatrix's arms, only to be pushed away.

"What are you doing with him?" Bellatrix asks coldly.

Andromeda notices that Bellatrix is wearing a black cloak and that her wand is drawn. Something lodges itself in Andromeda's throat. She knows that her older sister hates associating with Muggle-borns, but surely she wouldn't resort to something as destructive as setting fire to an entire village...

"Helping him," Andromeda answers feebly. She bends down to Ted, who is staring wide-eyed and terrified at Bellatrix.

"You--" he gasps, his eyes warily trained on her wand.

"Me," Bellatrix says, sneering. She playfully turns her wand around with her fingers as if it were a baton--as if she were taunting Ted, Andromeda thinks, alarmed.

Bellatrix's shiny red lips curl into a disdainful smirk. Andromeda doesn't know what comes over her. All she knows is that she can no longer stay on Bellatrix's side. She is only vaguely aware of the unfamiliar ache that spreads through her as she looks on Ted's face streaked with dirt and the blood that Bellatrix desperately wants to see destroyed. But the feeling is enough to make Andromeda Petrify her sister.

She drops her wand at what she has done and crumples to the ground.

"An...dro...meda," Ted whispers. He is resting on his elbows and slowly pulling himself to where Andromeda is crying. He stops when he is right beside her.

"Ted," she moans softly.

"You can lean on me if you want," he says, bringing his shoulder closer to her chin.

Andromeda accepts his offer gratefully. She allows herself to put her full weight on his shoulder and breathe in the smell of trees and fire. She decides that she likes the unspoken conversations between them the best.