Author's Note: A short drabble that entered my head and insisted on being written.

Disclaimer: I'm obviously taking a lot of creative license with Luna Inverse, how her powers work, and her knowledge of the magical. But let's face it, practically everyone does.

Timeframe: First Battle with Shabrinigdo (Anime Season 1)

~BD

Migraine from Hell

She was washing dishes when it happened – when an odd, ugly, horrific surge of power skated up her spine to crackle at the base of her skull.

She froze. Her jaw clenched and her teeth locked as sharp pain seared behind her eyes. The plate in her hands crashed to the floor and shattered.

She had known the night before that something terrible had happened, for the extraordinary power that both belonged to her and did not belong to her flared within her, completely unexpected, just as she was about to go to bed. She had felt a twitch of sudden fear in her gut that was not connected to anything around her and made little sense. And she had racked her brain for the reason, coming up with only one explanation.

A thousand years ago, Shabrinigdo had been split into seven pieces, and those pieces had been sealed within humans, to be reborn throughout millennia, in a desperate effort to weaken the Dark Lord's power. The only explanation for a surge in Cepheid's power would be the awakening of one of the seven pieces of Shabrinigdo.

The concern and fear belonged to Cepheid, not necessarily to herself. She had accepted her unique role from the moment she had understood it as a very young child. Her life did not truly belong her and probably never would. She was Cepheid's servant, after all.

Of course, just knowing a piece of Shabrinigdo had been reborn meant she had been horribly restless throughout the night, completely on edge as she waited for sheer chaos to erupt around her.

But nothing happened. She felt only little twitches of power from beyond the horizon, but nothing more.

Why wasn't Shabrinigdo striking? Had he not realized yet that Cepheid's will still existed within the world? Or did he realize Cepheid's will still existed?

And why wasn't Cepheid demanding she strike first?

Despite her normally cool exterior, she developed a splitting headache that pounded furiously behind her right eye, as she tried to formulate some answer for both Shabrinigdo's silence and the remnants of Cepheid's silence. Perhaps she had misread the situation? Perhaps Shabrinigdo had not been reborn?

No. She doubted that, her instincts were particularly sharp and refined because she carried Cepheid's will, and she was rarely (if ever) wrong.

The next morning, the combination of lack of sleep and horrendous migraine meant that she was unable to perform simple, daily tasks for the first time in her life. She kept dropping things and stumbling around, until her boss became so concerned that he told her to get back to the kitchen and rest for a bit.

But she couldn't rest, which was why she'd started washing dishes. She had to stay busy, keep her mind busy. Sitting around, doing nothing... it just didn't suit her. The questions kept reeling through her mind: When would she have to leave? Should she have already left? When would she be forced to fight a monster that could not be killed by humans, and which had barely been subdued by the gods? Would Cepheid's lingering will be enough to subdue one-seventh of Shabrinigdo? Would she be powerless or successful?

Why hadn't the will of Cepheid ordered her to leave yet?

And that was when she felt the bizarre, eerie surge of power in her very bones, and dropped the plate to the floor.

It was truly disturbing magic... unlike any she had ever felt before.

The frustrating thing about being imbedded with Cepheid's power was that she felt slight fluxes of magic whenever a sorcerer or sorceress was near... and she always felt magic whenever her incredibly powerful but reckless and annoying little sister fired off a particularly big spell. It happened regardless of distance between them; five feet or five hundred miles didn't matter in situations where Lina was concerned. A Dragon Slave would create an annoying blip in Luna's day (or night) that she could have easily lived without. On the other hand, it did serve as an effective radar to let her (and by extension, their parents) know that Lina was alive, since the little brat couldn't be bothered to write home more than once every month or two.

Only... this particular moment was not just a little blip. It was something much larger than just a Dragon Slave, which was just as confusing as everything else.

She abruptly realized why Cepheid's will had not ordered her to leave and find the reawakened seventh of Shabrinigdo...why Cepheid had not ordered her to attempt to destroy that single, powerful piece that had been revitalized. It was because Lina was involved, and Lina had just fired off something much, much more powerful than her usual magic. A Dragon Slave wouldn't have defeated Shabrinigdo anyways, and Lina would have known that much – she hadn't earned a color at the Academy for nothing. She was reckless and brash, but not stupid. A Dark Lord could not be defeated with his own power. Which only meant...

Luna Inverse sank to her knees and gripped the countertop above her as she tried to stop the blackness from creeping in on the edges of her vision. If she were in this fight, she wouldn't be battling chemicals in her brain right now! The wood splintered beneath her fingers from the power that wasn't entirely hers but made her impossibly strong just the same. She tried to anchor herself; she took deep, steadying breaths and she tried to sift through the sparks of power and magic to determine what was going on. She tried to ignore the nausea, the way her vision warped, the darkness that swirled threateningly in the corners of her eyes.

Logic, she thought desperately. Stay logical, Luna. Don't panic. Don't black out. What was more powerful than a Dragon Slave? What spells called on power stronger than Shabrinigdo?

Well, there was a starting point. She knew of only two spells more powerful than the Dragon Slave or the Elmekia Lance – spells that were never talked of within the Academy. Both spells in question were hidden from all students... hell, they were even hidden from most professors and mages who taught at the schools. Leave it to bloody fucking Lina to find such forbidden spells, Luna thought furiously. Lina would have found them, of course she would have! The Academy had awarded her a fucking color at the age of twelve, for gods' sakes, and color mages had more privileges than normal sorcerers and sorceresses.

But if Lina had used the most powerful spell, that meant she didn't know about the one between the Dragon Slave and the Giga Slave, and Luna felt a wave of anger coil from her stomach to her chest. Because that meant Lina had just risked destroying the entire motherfucking world because she hadn't learned of the Ragna Blade yet, damn it all! It also meant that Lina didn't know the true potential of the Giga Slave! What the hell was her sister doing? Sloppy research, that's what it was, and when she got her hands on that girl, Luna would kill Lina herself. It didn't matter that Claire Bibles were hard to come by, or that Luna could have given Lina the information herself - Lina never asked.

More wood splintered beneath Luna's fingers as anger coiled and seared through her chest. She was going to murder Lina, she really was, and Lina deserved it –

"Luna?!"

Her mother's voice interrupted her fury. Luna immediately forced herself to refocus on her surroundings instead of the conflicting waves of cosmic power and terror. The kitchen floor swam into view; shards of ceramic and wood had cut her fingers and hands, there were splinters of pulp everywhere, and blood from her cuts dripped to the floor.

"I'm fine," she gritted out, pushing herself to her feet and grabbing the counter again to stay upright. She swayed, but her mother did not come near her – her parents had always been slightly fearful of what she could do and knew better than to interfere with Cepheid's will. The only reason her mother was here now was probably because she had felt Luna's power rise, even from her shop across the street.

"You're bleeding!" Her mother's look was reproachful as she stood in the doorway to the kitchen and kept her distance, her hands slightly spread as if ready to cast a protection spell if necessary. "What on earth happened?"

"Lina, of course. Lina's what's happened. It's always Lina! What else is there?"

"Plenty else," her mother reasoned calmly. "Because Lina generally avoids angering you out of fear. And she's nowhere near us."

The less her parents knew about Lina's deadly adventures, the better. Luna took a deep breath. The fear was subsiding, the strange surge in power was ebbing away. Cepheid seemed aware that the threat was gone, that one-seventh of Shabrinigo had been destroyed. Lina had been exceedingly lucky.

"She fired off something rather large, that's all," Luna replied, ignoring the way blood ran down her fingers to drip to the floor. "It caught me off guard. She'll pay for it later; I do hate being caught off guard."

She could tell her mother didn't buy it.

"But a Dragon Slave has never bothered you this much before. There's nothing else larger than that, is there?"

Luna gnashed her teeth. Their mother had not earned a color like Lina, despite her sharp intelligence and extensive magical training – which meant she likely didn't know about the forbidden spells created to harness the power of the Lord of Nightmares. So Luna carefully replied, "It wasn't a dragon slave. Never mind what it was. It was worse, let's just leave it at that."

"Is she alright?" Her mother's question was calm, but Luna could still hear the underlying worry.

"I'm sure she's fine. Probably exhausted, but fine." She rather hoped her sister was exhausted. She rather hoped Lina had a splitting migraine and could barely walk, but she didn't voice this out loud. "If she were dead, I would know."

Her mother nodded once. "Very well. In that case, either heal yourself or let me do it."

"You'd best do it," Luna answered grimly. "I've got a migraine from hell and I can't seem to focus, which is pissing me off even more." She hated even admitting it, but it would be best if her mother did things properly.

Mrs. Inverse smiled and came forward at last, the relief visible in her face, and took Luna's right hand in her own to start casting a healing spell. "Don't be too harsh on your sister when you see her again, Luna. She tries so hard to please us. Including you."

Luna ignored her. Harsh her ass. She'd be worse than harsh, unless Lina did something stupendous to get back in her good graces.

But then, if Lina had correctly fired a Giga Slave and destroyed a seventh of Shabrinigo... perhaps she already had.