Summary: In the third year of the war, Draco is discovered as a spy for the Order of the Phoenix. Snape brings him to Grimmauld Place for safety. But months of being locked in a house with Potter take their toll, and soon both boys are in over their heads.

Pairing: Harry/Draco. If you don't like it, don't read it.

Warnings: Unbetaed, all mistakes are my own. Sexual content. Language.

Disclaimer: Harry Potter and everything affiliated with his world belong to J.K. Rowling.

Draco swore at Harry. Before Harry had dashed off, he left something in Draco's hand. Draco glanced down quickly and saw that it was a vial of basilisk venom. Harry had come prepared. But that still left the problem of him not having a wand. Draco slipped the vial into a pocket, intending to run into the Dining Room, find Potter and get his wand back the Muggle way.

The vial clinked against something in his pocket that hadn't been there before. Bewildered, Draco found himself pulling out an eleven inch Holly wand. For some reason known only to Potter, he had switched their wands. Draco couldn't fathom that reason, for it just made the pair of them more vulnerable. Your magic wasn't quite so strong with someone else's wand, everybody knew that.

Draco grasped the wand and tried a few simple spells; Wingardium Leviosa, Lumos, and Accio, and they all worked. Just about as well as his wand did, actually. Who knew, but Harry and Draco had compatible wands. Draco still didn't know why Harry had felt the need to switch their wands, but at least he had a decently working wand. He squared his shoulders and entered the dining room.

It was chaos. The beautiful dining room that his mother had worked so hard on was in ruins. The grand elf-carved oak table was in two big pieces. A curse had hit it in the middle and severed it. The spot where the curse had hit was still smoking slightly. Draco swept his eyes around the room, and noticed the blackened and burnt art on the walls or the floor by this point. There were curses flying, and Draco threw himself to the floor and barely missed by hit by a stunner.

The only way to tell the sides apart was the masks. The white masks shone brightly, even in the very dimly lit room. The Dark Lord was clearly visible, but Harry was not. At least, not until Draco looked closely. Then he noticed the spells fired from seemingly nowhere. Seeing Harry jolted Draco and he remembered what he was supposed to be doing.

Apparently Harry had abandoned his plan for them both to take down the snake in favor of fighting. Draco sighed, and moved out of the way of another curse. He squared his shoulders and started moving towards Nagini's room.

He kept to the edges of the room, deep in the shadow. Most of the candles and torches had been extinguished and the main lights came from spells and curses.

The Dining Room was really frightfully crowded. Granted, it was big, but it seemed quite small when there were fifty people fighting. Draco was focused on his path in front of him, and a fighting couple nearly crashed into him. Fortunately, he managed to jump out of their path just in time. He saw the Death Eater's eyes widen behind the eye holes of his mask, as if he had seen Draco outlined on the scorched wall.

The pair crashed into the wall and Draco heard a wand snap. Draco surreptitiously cast a hex at the Death Eater's back. That allowed Lupin to slam the guy's head into the wall and steal his wand. Lupin then dashed back into the conflict without a second glance.

Draco inched along the wall, only one eye on the path in front of his this time. The other eye was on the fighting going on to his right. So he noticed when Weasley and Granger showed up a door on the other side of the hall. He noticed Aunt Bella fighting with Tonks, and saw Tonks go down to the sounds of his Aunt's maniacal laugh.

Draco did not notice, however, that he had slowed down. He was moving at a snail's pace, most of his attention on the battles raging around him. He knew he was avoiding facing that snake, but that didn't stop him from slowing down. He sent surreptitious hexes and curses at the Death Eaters. He saw quite a few Death Eaters that should have been incarcerated. Apparently the Ministry and Daily Prophet had covered up another Azkaban breakout.

He wasn't the only one firing curses from seemingly nowhere, and he watched as the start of the curses moved closer and closer to him.

When Harry was standing right beside him, he spoke, "Draco, get going, we need to kill that snake."

Draco hissed back. "Why don't you do it, then?"

"I've already destroyed a Horcrux."

"Your point is?" Draco cast a Protego around Harry, and the hex that had come flying towards him bounced harmlessly off.

Harry sighed. "Thanks. But Nagini knows me, knows my scent, she won't respond to me even in Parseltongue…"

"She knows me too! I used to live here."

"Yes, exactly, you were a Death Eater. She'll be less hostile to you. I'm her master's sworn enemy!"

Draco growled. He hated it when Harry used logic. It was more annoying than when Granger used logic. Gryffindor's shouldn't be allowed to.

Draco didn't give Harry the satisfaction of an answer, just turned tail and walked towards Nagini's nest. His determination and bravado gained from his talk with Harry lasted him all the way to the door of Nagini's room. On his way he had dodged several hexes and what looked like a Cruciatius curse.

Finally he was standing outside the door, hand hovering above the knob. He did not want to do this, oh how he did not want to do this. Words could not convey how much he did not want to open the door and confront that snake.

Draco could hear Nagini hissing, even over the noises of fighting, and he shivered. Draco closed his eyes, and grasped the doorknob. He could do this. He was simply taking revenge on the snake, and on Lord Voldemort. That was it.

Draco turned the knob, excruciatingly slowly. Finally he heard a click and the knob stopped. This was it, now all he had to do was open the door. Even slower, he slid the door open. After a tense minute, the door was open enough for him to press an eye to the crack.

Nagini was curled up in the far corner of the room, apparently asleep. Draco breathed a sigh of relief and opened the door wider. He stepped in carefully, never taking his eyes off the snake. When something crunched under his foot, Draco jumped.

He looked down to see bones of rats, birds, cats and a jaw that looked remarkably human. Draco shivered and looked back up. That was a bad idea. Well, actually, looking down in the first place was the bad idea. When Draco raised his head, he saw Nagini wide-awake and looking at him. Her eyes glowed and Draco heard a hissing sound issuing from behind her fangs.

Draco told himself to move, to get out the room, to run, to anything, but his body didn't listen. Nagini wasn't a basilisk, but Draco felt like he was petrified. The hissing got louder as Nagini drew closer, drowning out the noises of fighting.

It wasn't until Nagini was less than two feet away that Draco reacted. He snapped back into it, and yelled, "Protego." Nagini ran right into the shield and hissed, looking very angry. Draco kept his shield charm strong as he tried to think what to do.

Until now it had seemed like an abstract concept, killing Nagini. He would enter her nest, kill her and get out. But now he faced a problem. How to actually do the deed. He wasn't able to cast Avada Kedavra on Dumbledore when his mother's life was in jeopardy. He doubted he could cast it now. There was no way her could stun her than kill her the muggle way, Draco wasn't touching that snake for all the gold in Gringotts. Well, not for half the gold in Gringotts.

Draco's mind was blanking on what spell to use. All those years as a Death Eater and studying under Lucius Malfoy and it came down to this. When he was faced with a hissing and spitting snake circling him, he couldn't react.

The only spell that was coming to mind was Sectumsempra, that curse Potter had used on him in the bathroom with Moaning Myrtle. Draco supposed he could let her bleed to death. Steadying his resolve, Draco lifted his wand and lowered the shield charm. In the three seconds before he finished saying Sectumsempra, Nagini got even closer, much to close for comfort.

But then the curse hit, and her blood was flying everywhere. Draco cast Protego again, but wasn't quick enough to stop the first bits of blood flying onto him. The shield charm proved to be a good precaution because Nagini didn't stop, even as she was bled dry. She ran into the shield charm again. She didn't hiss quite so loudly this time, and Draco took it as an encouraging sign.

However, Nagini didn't die, either. She had lost a lot of blood, so much blood. "There can't be any more blood left in her," Draco thought desperately, but there was. It just wouldn't stop.

Draco dearly wanted to leave, and say his job was done. But he just knew that if he left, somehow the snake wouldn't die, and this traumatic experience would be all for nothing. So he gritted his teeth and watched as Nagini's blood left her body, drop by drop.

Nagini was thrashing around, and her blood was dripping all over the place. The shield charm protected Draco from Nagini, but it couldn't stop the tangy smell of blood from reaching him. Draco forced himself not to look away. Finally, Nagini's movements slowed and then finally came to a stop. To Draco it seemed anti-clamatic, and then he realized. He took the vial of basilisk venom out of his pocket. A small corner of his mind wondered where Harry and Granger had gotten basilisk venom, for it was incredibly rare.

With careful hands, Draco uncorked the vial. Draco made sure his hands weren't shaking as he lowered the shield charm. Draco took a deep breath, and turned the vial over so it spilled all over Nagini's dead body.

There was a piercing shriek, and Draco turned away and covered his ears. When the noise was gone and he turned back around, instead of Nagini's body there were charred remains of a snake. Draco had done his job; the Horcrux was destroyed.

There was only the Horcrux inside Harry left. Draco wondered how Harry would destroy that. Maybe Granger would come up with something. Draco knew that Harry would destroy the last Horcrux, Harry would never leave a piece of the Dark Lord's soul lying around undestroyed. The question was how. And did it really make sense to destroy the Dark Lord's body when he wasn't completely mortal?

Suddenly it felt like someone had drenched Draco's insides with a cold bucket of ice. He shook his head, trying to banish the though. Surely Harry wouldn't, he couldn't be that self-sacrificing. The little voice in Draco's head pointed out that Harry was that self-sacrificing. He would probably kill himself if it meant destroying the Dark Lord once and for all. Harry had a saving people thing.

Draco ran out the door into the chaos of the Dining Hall. He had to stop Harry.