Disclaimer: Not JKR, not making any money

Severus fled the battle when the Order unleashed their Patronuses, when they ringed around Dankworth Manor and cast those great shields of white light. He didn't want to. He swore he had seen a flash of red hair in the crush of the melee, and the thought of her somewhere in the manor filled him with a fury he had only barely managed to Occlude away.

He hadn't been a part of the battle, not really, and so there had been no way for him to protect her somehow, no way to send her off to one of the secret locked rooms of the manor. No, he had to stand by the Dark Lord's side and watch, because he was one of the Inner Circle, and the Inner Circle did not fight.

They could be treated as shields, of course, standing between the Dark Lord and destruction, but they did not fight.

When the Opposition blasted the manor with the strength of their Patronuses, and the Death Eaters all scattered like insects, the Dark Lord grabbed Severus's arm and hissed, "I won't have you dead."

And he looked hard in Severus's eyes and the shields knitted themselves up so quickly that for a moment Severus almost forgot Lily himself.

"Go," the Dark Lord said. "Now."

And Severus did as he was told, because he could not defy the Dark Lord in the moment of retreat. He intended to Apparate home to Spinners End, but when the ink cleared he was standing on an unfamiliar street, the air still and cold, icicles hanging like daggers from the street lamps.

Severus exhaled a long white breath and let the shields unwind. Rage gripped him, and terror, and hopelessness. He needed to track her, needed to see if she was at least alive. And he needed to figure out why the fuck he had Apparated here instead of his front yard.

It was late enough and cold enough that no one was out, but the street looked more Muggle than magical. Severus slid off his Death Eater mask and tucked it inside his robes, then crept along the icy sidewalk looking for an alley or a shadowy corner or something.

And then he realized he had been to this street before.

It was the street where Lily lived - he recognized the old brick building he'd gone to when he came to heal her arm. It looked different in the dark, and covered with snow and ice, that's why he hadn't noticed right away. His thoughts of her must have tainted his Apparation.

He didn't know which window belonged to her flat, but it didn't matter, because all the windows in the building were dark.

Severus let himself into the building with a tap of the wand to the front door's Muggle lock, then wound quickly up the stairwell to her flat. He banged on the door. No answer.

For a moment, Severus didn't know what to do. Should he sit in the hallway for her to wake up - or come home, if that was the case? (He hoped it wasn't.) What if she was dead? He couldn't risk casting the tracking spell out in the open, not even in an empty Muggle hallway. He could Apparate back to Spinners End, but some vulnerable part of him not Occluded into nothingness didn't want to leave.

Severus hunched over her door, keeping his wand half-hidden in the sleeve of his robe. If anybody came out he could Confund them, but he would just as soon not deal with the hassle.

She had a charm on her door, a small one, and another slightly stronger ward. None of it Dark, of course, and Severus was able to break them both easily enough - although he did cast a quick repair spell once he was inside. He felt vaguely uneasy about breaking into her flat, but the moment he was through the doorway, and he could smell her on the air, all he wanted was to gather her up in his arms and tell her that she was safe.

If she's safe.

Severus slipped into the bedroom, but it was empty, the bedsheets smooth and unrumpled. Panic flooded through him, and that rage again, blinding and hot as the sun. He built up his shields just so he could concentrate.

He cast the Dark Lord's tracking spell over her bed, the light filling her room with eerie, crawling shadows. It took him about five minutes - five minutes during which his Occlumency built mazes inside his head, locking everything way - but eventually he found her. In Taiwan.

He sighed and slumped back on her bed, the spell still glowing above him. She's alive. And in a safe house somewhere, too - he checked the spell again, and it had her on the American Atlantic coast this time.

Hopefully she wasn't hurt. Even though he knew damn well that Death Eaters did not merely hurt. Which meant she was probably all right.

Probably.

He left the spell hanging in the air like a curtain of light and curled up on top of her bed, pressing his face into her pillow, which smelled like her hair, which smelled like her skin. He didn't take down his shields. He knew the sort of pain that was lurking inside of him: pain like a knife sawing out your heart, pain like watching someone die. And so he kept himself empty. He didn't think about Lily, he didn't think about the Dark Lord, he didn't think about anything at all.