When the familiar squeezing sensation of Apparation faded, Severus found himself in a musty, cluttered attic.
Luna let go of his arm immediately and began walking around the periphery of the space, chanting to herself. Severus recognized some of the spells as warding charms, but others were unfamiliar.
Since he didn't want to interrupt her, he surveyed his surroundings carefully. The space was perfectly round; they must be in a tower of some sort. The roof line peaked at seven feet in the center of the attic and sloped down to three at the edges. Two skylights lit the space.
The whole area was a mishmash of assorted junk: old furniture, some of which was rickety and some of which was sturdy and beautiful; boxes of all shapes and sizes; a few bookcases; a stack of framed photographs; a tower of large cans.
"I cast the Fidelius charm. You probably should know where you are so you can get back if needed." Luna had appeared, unnoticed, at his elbow.
"This attic may be found at the top of Rook Tower, located outside Ottery St. Catchpole."
Snape scowled. "Just the attic?"
Luna smiled mistily, picking up a photograph from the stack and handing it to him. "My father won't miss the attic. He would miss the whole house if it disappeared."
The frown lines on Snape's face deepened. "You expect me to live in this attic for the rest of my life?"
"Just a year. But it's all set up, you see. Well, the furniture will need a bit of rearranging—but everything you need is here. Bed—" Luna waved her hand at a double-sized sleigh bed, complete with sheets and comforter. "Self-filling water pitcher, hot plate, self-emptying chamber pot—"
"And food, I hope?"
Luna indicated the stack of cans with a wave of her hand. "Right there. One year's supply: just add boiling water. Daddy believes that civilization will end soon, you see, so he's always had food on hand for us. This particular batch was for my mother…"
Severus looked down and noticed, for the first time, the picture he held: that of a young lady who looked remarkably like Luna. It was, of course, her mother, Lavinia, who had been two years ahead of him at Hogwarts.
"All of these are her things, you see," continued Luna. "Daddy couldn't bear to look at any of it, so he put it all up here. He never comes up here; he won't miss the attic at all. It's hard enough for him, knowing that I have a picture of Mum in my room."
"I have no wand."
"Yes, but you won't need one, will you? Everything you need is here. The bookshelves are enchanted, by the way—you just ask them for what you want, and they will send something of the sort from the library downstairs. All of our bookshelves are charmed that way."
"Potions manual," Severus proclaimed as a test. A tattered copy of Advanced Potion Making and a dusty looking A Potions Master's Herb Lexicon appeared before him. Well, it wasn't quite what he'd hoped for, but it would do.
"I'll try to get you other things to do, but I'm not sure what I can manage. The skylights are operable, by the way, in case you want fresh air. Just watch out for the Nargles—they've been known to get into the house that way sometimes."
With this pronouncement, Luna twirled on her toe
"Wait!" cried Severus. There were so many questions yet unanswered. He reached out to grab a hold of her, but it was too late; she'd Apparated away with a faint pop. He stomped over to the trapdoor in the center and tugged on it, but it was locked.
"Blast!" he growled. When he was frustrated, this was a literal pronouncement: smashing something with a good spell was extremely satisfying. He reached for his wand, but—curses! He didn't have a wand. Instead, he picked up the stuffed animals that littered the bed and flung them across the room. The frames of the photographs looked like they'd smash satisfyingly, but he had an annoying suspicion that if he did so, he'd be treading on broken glass for a year.
At last he collapsed on the bed, still annoyed. "This isn't much of a plan," he said to the pillow. And yet, in the back of his mind, he had a feeling that whatever scheme Luna Lovegood was cooking up would be quite clever.
Author's Notes: Sorry for the long delay—had a bad case of Real Life hit me. I do have an outline for this story, just as Luna does have a more elaborate plan than she's letting on.