In the end, Duncan did allow them to stay.

"He has somewhere to hide the muggleborns," Lily told James the next morning. "He just said that we stay at our own risk; if Severus Prince does come, he's going to deny all knowledge of your involvement in helping those muggleborns."

What she didn't tell James was that Duncan had seemed quite annoyed by the whole situation. He had told Lily that he would let them stay because he "wasn't heartless," but it had been quite a bitter statement.

"Well, why can't we hide with them?" Sirius demanded.

He had arrived almost at the crack of dawn, and had been perching in a chair near James ever since.

"They don't want someone with dragon pox hiding with them," Lily admitted.

The next two days passed painfully for Lily. She kept expecting Severus Prince to appear in the doorway, and each moment felt like a clock ticking down to that inevitable end. Worse than the suspense was watching James's health deteriorate. It started with some coughing and a few spots; soon his skin took on a green tinge, and the sound of coughing turned to the sound of laboured breaths. She tolerated Sirius's presence for James, but she almost could feel the accusation in his gaze, and so she found his being there unnerving.

"You don't care about him at all, do you?" he asked on the evening of the second day, when James was asleep.

"Of course I do," Lily said. "Just because you love him doesn't mean no one else does."

Sirius looked taken aback. "I didn't say I love him. Although I do… I mean, as a friend."

"That's not what I meant."

"Fuck off, Evans."

This conversation had one positive result, which was that Sirius was angry enough to storm off, finally leaving Lily alone with James. By then, there was nothing for Lily to do. Lily had given James all matter of potions to help with his symptoms. The green had started to disappear, replaced by a deathly paleness; this was the stage, Lily knew, where James would either survive, or he wouldn't.

She climbed onto the bed and curled up beside him, leaning her forehead against his. She put a hand over his hand, which was much colder than she was used to it being, and she considered, for the first time, that she might soon be a widow after only two weeks of marriage.

It was something she hadn't wanted to think about, but now, listening to his painful breaths, feeling the warmth of his fevered skin against her forehead, she finally faced the fact that James might not recover.

She had no concern for herself. She thought that if she was going to get dragon pox, she probably would have by now. Perhaps she had a natural immunity; perhaps the chicken pox she'd had as a child had actually been dragon pox, and her parents just hadn't recognized the signs. Whatever it was, she hated it; she would so much rather give any immunity she had to James.

Sirius had been right; this was her fault. In trying to help others, she had hurt the person who mattered the most to her. What, then, had been the right thing to do? Was it right to let innocent people suffer when she could have helped to prevent it? But was doing the right thing really worth such a cost?

She loved him. He had brought something to her life that she never could have imagined. It wasn't just emotional and physical intimacy, but a million other little things. She had been telling the truth when she told him that he made the bad things better. What would she do without him?

"Lily?"

She wiped quickly at her tears. "Sorry, I didn't mean to wake you."

"What's wrong?"

She couldn't very well tell him that she was upset because he could be dying.

"Nothing," she told him. "Go back to sleep."

He closed his eyes.

"I love you," she whispered, but if he heard her, he made no response.

She woke to urgent knocking on the door.

"Lily!"

She recognized Brian's voice, so she unlocked the door.

"Severus Prince is in the castle," Brian said in a rush. "He's looking for James. You should go hide with the muggleborns."

A chill went up her spine, but Lily folded her arms and said, "I have no reason to hide. I'm married to a pureblood."

Brian gripped her arm, hard. "Do you want to die, Lily? Because if you try to stop Severus Prince from getting to James, you're not just going to die, you're going to suffer first. He'll torture you. He'll rape you. Do you want that?"

"Let go of me."

He looked down in surprise, as though he hadn't realized that his hand was there, and finally released her.

"Please, Lily. You're Cait's friend. Think about the people you'll be hurting before you throw your life away. You know where the muggleborns are hiding, correct? I'll even escort you there and make sure you get to safety…"

"No," Lily said. "I'm staying with my husband."

Brian groaned. "Come on… Lily…"

"Thank you for the warning, Brian," she said gently. "It was kind."

She closed the door, leaning her back against the wood. Then, she took out her wand, and she waited.

Once again, Severus Prince was dressed all in black, this time with a long billowing cloak. In her imaginings, Lily had thought Severus Prince would burst into the room, wand drawn. Instead, he opened the door and stood in the doorway, one corner of his mouth twisting up into an unpleasant smile.

"Well, well. If it isn't the mudblood. Where's your traitor husband?" His dark eyes drifted to James's still form lying on the bed.

"He has dragon pox," Lily said. "I wouldn't come any closer, if I were you."

Sneering, Severus Prince drew his wand. "That's quite contagious. Given the circumstances, I'm sure the ministry would understand if I execute him without bringing him to trial, where he could infect others."

Lily stepped in between James and Severus Prince's wand.

"No," she said.

Severus Prince laughed. "No?"

Lily spoke rapidly, her heart pounding. "Severus… you remind me of someone. His heart was broken into a million pieces, and he thought that hurting other people would make it whole again. I don't know what happened to you to make your heart broken, but breaking other people isn't going to fix it."

Severus blinked at her. "Excuse me?"

"Muggleborns are people, too," Lily said. "You can't really believe that someone is less than you are just because of where they came from, can you? I know you have some goodness in you. Everyone has goodness in them. And James is filled with goodness. Please… if you have any kindness left in your heart… please just let us go."

Severus Prince's expression softened. He moved towards her, and Lily resisted the urge to flinch away.

"You really believe I can be good?" he said quietly.

Lily nodded. "I think anyone can be good, if they choose."

For a brief moment, Lily thought she'd won. She had actually gotten through to Severus Prince-

Severus Prince punched her in the stomach, hard, and Lily doubled over, gasping.

"Do you know what I choose, mudblood?" he hissed in her ear. "I choose not to be good."

He shoved her to the ground, but she kept a tight grip on her wand and pointed it his way.

"Expelliarmus!" she gasped.

"Protego!"

In a flash of light, her spell rebounded. With a cry, she sent another spell towards him.

"You think," he snarled, deflecting it, "that I would lose to a mudblood a second time? There's no pureblood around to save you this time, mudblood…"

Rage coursed through her, and for the first time, Lily went on the offensive, rather than defensive. This time, it was Severus Prince who struggled to dodge her spells, whose face went into a satisfying arrangement of disbelief as his wand finally flew from his hand, hitting the wall behind him before clattering to the floor.

He held his hands up slowly, and then he began to laugh.

"So you're going to kill me, mudblood? You should know that there are many witches and wizards searching this castle. You may kill me, but you won't kill our noble cause. You'll both still die."

Lily was tempted, then. She had never wanted to kill anyone before, but Severus Prince was the sort of person who objectively deserved to die. He was a sadist, a fanatic, a monster. The world would be better without him in it. He had caused the deaths of countless people, and would no doubt cause the suffering of many more. Even her former fondness for Severus Snape was almost not enough for her to spare him, not now, not when him being alive was a significant threat to her and James's existences. But still she hesitated, and his laughter crescendoed.

"No, you're too much of a coward," he said.

"On your knees," she said coldly.

He fell to his knees, his laughter abruptly stopping. He looked up at her with his dark eyes, so devoid of warmth and humanity, and Lily still couldn't help herself; she felt pity.

"You may choose to be evil," she said quietly. "But I won't. Petrificus totalus."

He fell to the ground, his limbs frozen. With her foot, Lily shoved him under the bed, just in time for Sirius to burst in. When he saw her with her wand raised, he relaxed.

"I heard Severus Prince was on his way here. We need to get James out of here," Sirius said.

"Agreed."

Lily moved towards the bed, surprised to see that James was already awake. She felt a surge of guilt; how much had he seen? Had he witnessed her sparing Severus Prince yet again?

"Let's get you up," she said, hoisting him to his feet.

"Accio brooms," Sirius said.

As they waited, James leaning heavily against Lily, Sirius looked at her oddly.

"What?" she finally asked.

"You didn't leave to hide," Sirius said.

"Of course not."

"Lily's a bloody hero," James muttered. "Fought Severus Prince and won. He fled."

Sirius stared. "Really?"

Two brooms finally flew through the door. Lily helped James onto one, climbing on behind him to hold him in place.

"You're going to laugh," she murmured in his ear. "I'm a terrible flier. And I'm scared of heights."

"You're not."

She wrapped her arms tightly around him, and then kicked off from the ground. They both ducked as they flew threw the window and out into the night, leaving the brightly lit castle, with all of its friends and foes, behind.