"Choose a side, Malfoy," Harry said and raised his wand. "Good or evil."
Draco looked at Harry. "I choose your side."
Harry's wand shook in his hand. "How can I believe you?"
"Like this," said Draco. He spoke three words in a long forgotten tongue and bound himself to Harry with an oath that could not be broken.
Harry stared and it was half a minute before he lowered his wand. He stepped closer and put his hand on Draco's shoulder. "Why?"
"You need my help," Draco said and covered Harry's hand with his own.
"How can you help me?" Harry said later, underneath the stars and the curve of Draco's arm.
Draco's mouth was on Harry's cheek and his voice was hard to hear. "There's more you need to know, if you're to defeat him. I can teach you."
"No," said Harry.
"You have to," said Draco. "There is no other way."
"No," said Harry again, but his side was doing badly and why else had he come to Malfoy in the first place?
"Let me," Draco said, and kissed him.
The others distrusted Draco at first.
"He gave his oath," Harry said.
"Give him Veritaserum," Ron said. "Question him."
"No," said Harry. "That's not right."
But Draco disagreed. "Use the tools you have," he said. He drank it down and Hermione asked him questions.
"He's loyal," she told them. She sounded disappointed.
After that, they trusted Draco. But they didn't like him.
Harry was distressed.
"It's all right," Draco told him. "It's the work that matters."
They studied in the evenings. Harry was always tired and Draco was patient with him.
"This isn't right," Harry would say, whenever Draco taught him something new.
And Draco agreed and rubbed Harry's neck, waiting until Harry was quiet. "Someone has to know these things," Draco said. "Can you ask anyone else to learn them?"
And they would begin again.
At night, they slept close together, Draco curled around Harry in their narrow bed. Often Harry dreamed and woke, shaking. Draco held him and whispered soft words into his ear until Harry drifted off again.
Sometimes Harry turned to Draco and they made love in the dark. But more often Harry was too tired. "I'm sorry," he said.
"Shh," Draco said, stroking Harry's face. "Sleep. We'll have time later."
And Harry slept, Draco's arm around him.
During the day, they worked with the others, devising strategy against the enemy. Harry's plans became more daring, more dangerous, and some objected to them.
"Our people will die on this mission," Hermione said.
Harry looked at Draco, but he was silent. "This is war," Harry said. "We're spending lives for lives. Our goal is to make the enemy spend more than we do."
No one met Harry's eyes and so he returned to the briefing.
Harry sent his people out and not all of them came back. But their gains were greater than their losses and they toasted their dead before the next sortie.
Harry made gems for his people, crafting them with Draco's help, setting them with charms. Draco had a light touch and the gems were small and beautiful, full of light.
"These will help us," Harry said. He took each of his people by the hand and pressed a gem into their palms. It sank down until it was a soft glow beneath the skin. "I will be able to track you, communicate with you. If you are taken, the enemy will get no information from you." He stood in front of them, the ones who remained. "It is my gift to you, my pledge that I am always with you."
They cheered for Harry and he raised his arms to them.
Draco already had his gem and it shone red inside his hand.
Harry was stronger now and less weary. He had exhausted Draco's knowledge, so they both studied now, and Draco smiled to see Harry surpass him.
They spent long hours in the dark, talking and holding each other close. Harry no longer woke in the night and he slept with Draco warm against his chest.
And then the last day was upon them. The weak were gone; the strong faced the strong. Draco did battle with his own father and killed him and left his body broken on the ground.
Then he stood at Harry's side and together they used the enemy's own arts to bring him down. When it was over, Draco picked up Voldemort's wand and made as if to break it.
"No," said Harry. "Give it to me."
"As you wish," Draco said. He took Harry's hand, put the wand into it, and watched Harry grow electric with power.
"My lord," Draco said, and smiled.
FINIS
Oh! Surprisingly evil, both of them. A supreme ending.