Author's Note: So. This is the story where I blatantly disregard the fact that the Sarah Jane Adventures are actually set a year after this, basically for the sole reason than that it's a really good story like this.

Sorry if that bothers you.

But... seriously. It's a really good story.

See if you can guess the villains. They're not based on the Whoverse or Buffyverse, but an English major could probably work out who and what they are.

(If you're a new reader, and don't know who Seo or Alison are, don't worry. You'll find out.)

The girl in the school uniform stumbled into the public toilets, tears in her eyes, the panicked rasping of her breath tearing through her throat. She grabbed at the sink, her arms shaking, and only then seemed to notice the bloodstained knife in her hands.

"Oh, God," she breathed. She dropped the knife into the sink. "Oh, God. It was real." She looked at her hands — covered with someone else's blood. "That was all real!"

Her legs gave out from under her, and she collapsed to the ground, sobbing, trembling, curling in on herself, not able or willing to face the truth.

"I can't have," she said. "I can't have possibly…! I couldn't have…!"

The door slammed open, and another girl rushed in. One not attired in the school uniform — a girl with blond hair, brown eyes, and freckles. She knelt down on the floor, beside the uniformed sobbing girl, gently shushing her, trying to calm her down.

"My name's Seo," she told the girl. "I saw what happened. I can help."

"I… I didn't… I couldn't have done it," said the girl in the school uniform, still staring at her bloody hands. "I couldn't… have…" Then shot her head up. Blinked the tears from bloodshot eyes.

Seo's soothing hands froze, just for a second. As the two girls locked eyes.

"Murderer," said the girl.

"It wasn't you," said Seo, taking her by the shoulders. "You're not a murderer. Promise. You're…"

"You, Seosyrae," said the girl, pointing at Seo. Her voice dropped, becoming dark and icy and dangerous. "You killed your dad."

Seo's eyes widened, as she started back from the girl. "How'd you know…?"

The girl sprung forward, tackling Seo to the ground, hands around her throat. With a steel grip, she squeezed, her eyes almost glowing with the anticipation of the kill. "Pay for your crimes," said the girl, as Seo struggled beneath her. "Die for your crimes!"

Seo tried to get up, tried to get out of it, but… there was a weight pressing against her mind. A weight strangling her from the inside, just as the girl strangled her outside.

"Die, Seosyrae," said the girl. "Die for—"

The girl started back, suddenly, screaming. She jumped to her feet, eyes panicked.

"Oh, God," cried the girl. "Oh, God. Oh, God!"

Seo struggled to regain her breath, climb back to her feet. Then realized that the other girl had already grabbed up the knife lying in the sink.

"Don't!" Seo shouted, her voice raspy and scratchy. She lunged for the girl, trying to wrestle the knife from her hands.

But… too late.

The girl had already slashed the knife across her own throat.

Maria, Clyde, and Luke all sat scattered across the attic, looking down at the ground. None of them wanting to say anything.

"It's… aliens, right?" said Maria. She looked down at the newspaper in her hands. "Please make this be aliens."

"Sometimes," said Sarah Jane, with a sigh, sitting beside Luke, "humans can be far crueler to one another than any alien ever could."

They stared at the newspaper article. A murder suicide, at their school. Jason Gardner. Killed by Vicky Stuart. Who then killed herself in the toilets.

"I've seen him around," said Luke. "I didn't know him very well, but… he seemed nice." His shoulders slumped. "He shouldn't have had to die. Not like that."

Maria took a long, mournful breath. She'd seen Jason around, too. She didn't think he'd deserved to go the way he did. Not at all.

It was almost too much to think about.

"Why?" Clyde asked, looking up at the rest of them. "That's what I don't understand. That… Vicky… she was three classes up from him. Didn't even know him. So why?! Why did she do it?!"

"There must have been a connection," said Luke. "Something no one knew about." He'd read that in a book a week ago. Motive-less murders were extremely rare. Especially if Vicky had killed herself, afterwards, there had to be a reason.

"Unless they can track down the unknown witness," said Maria, "I guess we'll never find out."

Buffy sat on the couch, cross legged. Eyes staring, intently, at Seo, who was sitting at the computer, typing furiously.

"I know I can't stop you," she said. "But I can damn well try."

Seo didn't answer, just kept typing, her eyes focused on the screen.

"I mean it," Buffy insisted. "You just try setting one foot in that school, and you're going to come face to face with Slayer-Mom."

"Whatever this thing is, it's hiding in that school," said Seo. Her voice still raspy. "I'm the only one who can find it. So I have to. Before it kills, again."

Buffy gave a sigh. Knowing Seo was right. But she hated sending Seo to school, again, after last time. And she really hated sending Seo to a school she knew, for a fact, was out to kill her.

"Then you're not doing this alone," Buffy said. "I'll go there, too. Find a job. Or volunteer work. Or something. Make sure you're—"

"Helicopter parent, much?" Alison muttered beneath her breath. She scooted closer, on her rolly chair, trying to read the screen over Seo's shoulder.

Seo gave a small shrug, and shot Alison a sympathetic smile. "You can't join me, either."

"What?" said Alison. "Why not? You can add me as a transfer student."

Seo kept typing at the computer. Didn't answer, except to say, "Sorry."

Alison's eyes narrowed. "Then I'll do it myself."

Seo stopped typing. Turned to look at her mom and Alison. "This thing wants information," she explained, her voice tired and worn out. "About me. If you two are around, it'll get inside your minds. Figure out exactly who and what I really am. I can't risk that."

Neither one said anything.

Seo turned back to the computer, resuming her hacks into the school database, to add herself in as a new student. Her careful manipulation of facts and figures, memos and emails, anything she could access.

"So you just want us to… go about our normal lives," said Alison, "while you set foot inside a death-school that's harboring something hidden that wants to murder you."

"Yes," said Seo.

Buffy slid off the couch, cell phone in hand. "In that case, I'm gonna tell Torchwood I'm packing it in for the foreseeable future," she said. "There's no way I'm going to chance being three hours away when you wind up in serious trouble."

And Torchwood were going to be majorly pissed off about that. Ever since that thing… with Jack and the rift (and Buffy really didn't want to think about that any more than she had to)… Torchwood had been kind of relying on Buffy popping up on a semi-regular basis to eliminate serious evil.

But family came first.

"Did you ask Torchwood if they have any idea what this thing is?" Alison called after her.

"Yes, I did, and no, they don't," said Buffy, stopping in the doorway. She looked over her shoulder, at Seo. "And, just to show you how much I love you, I actually went into the Ministry of Defense to ask Giles about it. But he said he doesn't know what it is, either."

Seo stopped typing, spun around at her desk. "You went into…?"

"Yes, I did," said Buffy, gritting her teeth. Dear God, did Buffy hate political-type things! She sighed, tension dropping from her body. Then turned, and went to call Torchwood. "Giles says he'll let us know if he finds something out."

The moment Buffy left the room, Alison leaned in to Seo.

"She's freaked," Alison whispered.

Seo's eyes lingered on the distant figure of her mum, talking on the phone with Tosh — it sounded like — trying to explain the situation.

Then glanced back at Alison, and raised an eyebrow.

"All right, so maybe I'm a little freaked, too," Alison admitted. "But do you know how boring my life's going to become if you get yourself killed?"

Seo gave a small smile. Alison expected her to say something back — something typically nonsensical, off-handed, and clever at the same time, the way she usually did — but instead, Seo just grabbed Alison up into a tight hug.

Now Alison really was alarmed.

"You… think you're going to die," she realized. She pulled out of the hug, and held Seo by the shoulders. Noting the tremble running through Seo's arms. "You actually think—"

Seo gave her a perky grin. "Of course not!" she insisted. "Dying goes against most of my life goals."

Alison gave her a serious stare, and Seo rolled her chair away from Alison, hand rubbing the dark bruises still evident on her neck. The bruises that her mum had been telling her she should let heal, even though Seo had insisted on healing them 'the human way'.

For her own reasons.

"Don't do this," Alison pleaded.

Seo looked down at her hands, and gave a small shrug. "I have no choice."