Kogasa was the youkai of surprise. On normal days, she was a weakling. On normal nights, she became horrifyingly powerful. And on abnormal nights, she was nigh-omnipotent. On a night like this, she became a god of sorts; every trick anyone pulled on someone, every time a surprising trick was pulled, fed her like a prayer fed a god. And on Halloween, this reached its maximum output.
Against this, Sanae didn't stand a chance. The will of one teenage girl against a creature fed by the universal surprise of Gensokyo? An unlikely contest, though to her credit, one she took on.
Sanae leapt at Kogasa, her gohei shining a bright green in the dim. Wielding it like Youmu wielded Hakurouken, she attacked the youkai, who laughed and blasted her away with a surprisingly fast volley of blue orbs.
?You can't beat me tonight!? Kogasa laughed as Sanae slumped against the wall, sliding down, a slimy trail of her red blood clinging to the wall in her wake. ?Not tonight, when I have the power of a god! Tonight, I'm being fed the surprise of an entire nation!?
Sanae's eyes flew open. ?Gray Thaumaturgy!? she declared, shooting a volley of red and blue stars at her. Kogasa just laughed some more and batted them away with her umbrella.
?What the--? Kurumi stammered as she watched Kogasa zoom over and smack Sanae into another wall with her umbrella, hearing the sound of bone snapping. ?She's monstrous!?
?Don't just stand there, help me! Please!? Sanae yelled as she grit her teeth and slammed an amulet onto her broken right arm. In a flash of green light, her arm was whole again. Kogasa was suddenly there; Sanae gasped in shock. The youkai sneered and pulled her up by the hair, slamming her into the ceiling legs-first. Sanae screamed in pain as her legs shattered; Kogasa then dropped her to the floor as she sobbed in pain.
?Oh, it's you,? Kogasa said, looking bored as she glanced at Kurumi. ?The weak vampire. Just get out of here.?
?You're a stage two boss,? Kurumi muttered. ?How did you get this powerful??
?Faith is a powerful thing.? Kogasa smiled. ?Fear is stronger. Tonight, on Halloween, the dead are celebrated and death is itself feared. Death doesn't ask politely to make an appointment. It's a surprise. The best surprise of all.?
?You're insane,? Kurumi muttered.
Kogasa giggled. ?Well, maybe. Blame Yuka. Her energy is making me slightly crazy, if you will.?
?Rin, Pyō, Tō, Sha, Ka--?
Sanae had only begun to chant when Kogasa was suddenly there again, snapping her fingers back before she could make the nine syllable signs.
?Boo,? she said as Sanae screamed in pain. Kurumi winced.
?Are you just going to stand there?? Kogasa observed, kicking Sanae in the chest. ?You're not going to help at all??
?I can't help,? Kurumi said, her shoulders sagging. ?I'm weak. Just a stage two boss.?
?Hey, don't let being a stage two boss keep you from being powerful,? Kogasa snickered. ?It'd be surprising if you beat me, though, but that would just make me stronger, wouldn't it??
?Oh, how did I get mixed up in this?? Kurumi asked no one in particular, falling onto her knees.
?Eh, that's enough of that,? Kogasa huffed, wiping off her hands onto Sanae's shirt. ?Back to gathering more energy.? She walked back to the group and continued to drain them of their energy. Her umbrella was getting bigger and bigger, and a faint blue aura surrounded Kogasa as she became even stronger. She had to be at least phantasm-level by now.
?Hey... Kurumi,? Sanae whispered. ?Please... stop her. Somehow...?
?Stop your talking,? Kogasa snapped, turning to look at Sanae, who was crawling across the floor, her bleeding, broken legs leaving a trail of blood.
?Please,? Sanae begged. ?You have to stop her... save Gensokyo before Kogasa becomes too powerful...?
?I... can't,? Kurumi said. ?I don't have anything, no spellcards or power--?
?You have that spellcard Flandre gave you,? Sanae said weakly. ?Earlier.?
?It's blank, though,? Kurumi replied, pulling it out. ?I'm PC-98, I don't really understand spellcards...?
?What is that?? Kogasa asked, angry. ?I took everyone's spellcards away. You got one past me. Interesting.? Kogasa hefted her umbrella, holding it like a lance. ?Hand it over, or Sanae's going to get it.?
?Stop her!? Sanae yelled, closing her eyes and glowing with bright green light. When it cleared, Sanae was back on her feet, holding her gohei like a sword.
?Kurumi, charge her! You use that spellcard! I'll back you up!?
?A last stand, eh?? Kogasa grinned. ?Sounds like fun!?
?Rin, Pyō, Tō, Sha, Kai, Jin, Retsu, Zai, Zen!? Sanae chanted, her gohei lighting up with green fire. ?COME ON!? she declared, extending her hand to Kurumi. ?I know you can help me beat her. Let's do this together!?
Kurumi shook her head. ?I'm so weak, though.?
Sanae laughed. ?Kurumi, you're the only one I have left. Not even Yuka was able to escape Kogasa, but you did. And Kogasa is also a stage two boss. You can help me, Kurumi! I believe in you!?
The vampire blinked, looked down at the card, and then looked back up.
?... really??
?Really.? Sanae grinned. ?Now let's go and bring this bitch down.?
?... yes!? Kurumi nodded, taking her hand and getting back onto her feet.
Kogasa snickered. ?You're daring to challenge me? Okay.? She hefted the umbrella, facing it at Kurumi point-first. ?I'll kill you, just so you know.?
?I'm undead,? Kurumi pointed out, her claws extending. ?Remember, I'm a vampire! And we're full of surprises!?
Sanae nodded. ?Let's go!?
"Let's settle this." Kogasa charged forward, throwing her umbrella like a spear--Kurumi's shoulder exploded in a shower of blood. She grit her teeth and charged, her claws ready to slash--
?AAAAAAAAAAAAAA--? Kurumi screamed.
"RAAAAA--!" Kogasa howled.
"Sea cucumber!" Sanae said.
A hand-sized slug, presumably a sea slug, appeared an inch in front of Kogasa's face. It plopped on. Kogasa stumbled, ripped the thing off, and saw, too late, that Kurumi had the final blow.
She slapped her only spellcard onto Kogasa's chest. ?
LAST WORD!? she declared as Kogasa began to panic, and rightfully so. A hellishly bright red aura surrounded Kurumi as the spellcard lit up with energy.
?
VERMILION CITADEL - WAVE MOTION GUN!?
-----
Five minutes later?Good going,? Sanae muttered. ?I think you broke Gensokyo.?
Kurumi looked at the huge wall in Gensokyo's reality she had just blasted open.
?So it seems. So it seems.?
?... I'd better put it back,? the priestess said, waving her gohei.
-----
?So... Kurumi Scarlet really is your name?? Byakuren asked. They were sitting around on the Myouren Temple's roof, having a picnic. Kogasa was forcibly providing shade. She had been tied up and stretched out over the roof.
Kurumi nodded. ?Remilia is my cousin. And unlike her, I really *am* a descendant of Tepes.?
?My, my,? Yuka laughed, punching Kurumi's shoulder. ?Looks like you really are powerful inside, after all!?
?How surprising,? Kogasa muttered, annoyed. Murasa hit her with an anchor.
?I have to wonder, though,? Kurumi pondered as everyone else ganged up on Kogasa, using her as a pi?ata. ?Kogasa was possessed by an Elder God... but we didn't summon it. How did it get here...??
-----
?Ooh, tough luck, Yumemi. Azathoth has woken up. All investigators are devoured in a wave of... pure fun. Game over.?
Yumemi sighed and tossed her dice to Chiyuri. ?Geez, this new expansion is such a pain.?
?Could be worse.? Renko sipped from a cup of tea. ?We could live in a world where all of this horrible stuff was possible.?
?Good thing we don't live in a place that's powered by people's disbelief or something!? Maribel grinned.
In the background, Kana hung a lampshade and went to order some pizza.
I officially have no idea where I was going with this.

Regardless, Happy Halloween to all!
Though Serp did want to see me turn a funny story into a horror fic, then whiplash back to funny. I hope this is a step in that direction.