DISCLAIMER: I DO NOT OWN TOUHOU PROJECT!

"Are you sure that we don't have to wear dress clothes or anything?" Youmu asked Yuyuko as they headed out the door. Myon, Youmu's ghost half, floated around above them. It was exactly 7:57 PM and they were heading to the Scarlet Devil Mansion for the party.

"Yes, I'm sure. The invitation didn't include anything about it, and when we go to Remilia's occasional parties, normally she doesn't have us dress up," Yuyuko explained.

Suddenly, a cold wind tossed them around as they flew over the Forest Of Magic. "Brr...I'm cold, Yuyuko-sama..." Youmu shivered.

"Come here. We can keep each other warm," Yuyuko told her, drawing Youmu closer to her.

Youmu felt warmer when she was close to Yuyuko, despite the fact that Yuyuko's skin was normally ice-cold as a side-effect of being a ghost. Youmu kissed Yuyuko's cheek and they smiled at each other.

"Hey, I can see the mansion!" Youmu pointed at the magnificent-looking Scarlet Devil Mansion in the distance. It was a very large and red mansion, built with bricks and very fine building tools.

"I hope we'll arrive on time," Yuyuko told Youmu.

"Me too. I wonder if this party is just another one of Remilia's random parties, or if there's an event that happened to cause a party," Youmu replied.

They landed in front of Scarlet Devil Mansion gates and were both surprised to see Meiling awake, taking invitations from the residents of Gensokyo. Sakuya stood beside her with a clipboard, an important-looking piece of paper, and a pencil. When Yuyuko handed Meiling their invitation, Sakuya looked up, smiled at them, and then looked back down at the paper and checked something off.

It's probably a party guest checklist or something, Youmu thought to herself as two fairy maids pulled open the doors and two more led them down the hall to the ballroom, where Remilia and the other residents of the mansion normally set up snack tables, tables to eat on, and a stage, where the Prismriver Sisters would perform.

Every time Youmu entered one of the Scarlet Devil Mansion's many rooms, she couldn't help but gasp in awe. The building was built so expertly that Youmu always wondered how much all of this had to cost.

The Prismriver Sisters were on stage, playing a classy tune as the guests filed in through the ballroom entrance doors. Remilia was sitting at one of the tables with Flandre and Yukari, engaged in conversation. Yukari and Flandre both laughed super hard at whatever Remilia had said.

Yukari...Youmu thought, cringing. Every time Youmu thought about Yukari, she cringed. Everything about Yukari disgusted her. The way Yukari laughed, the way she smiled...even the way she fought in battle made Youmu cringe in disgust because of what she had done to her Yuyuko-sama.

Yuyuko laced her fingers with Youmu's, lightly squeezing her hand. "I know how you feel about Yukari. I feel the same way, but we mustn't act out in public or else it'll just cause more trouble. If Yukari starts bothering us, that's when we should react. But don't start a fight with her, please. The last thing we need right now is an angry Yukari bothering us," Yukari whispered to her.

"Okay," Youmu whispered back.

Remilia rose up from the table with Flandre, walking across the room to greet Yuyuko and Youmu. Ran and Chen had taken their places back at the table with Yukari.

"Ah, Yuyuko, Youmu! It's been a while, hasn't it? Well, anyway, welcome to my 501st birthday party! There are refreshments at the snack tables, so feel free to help yourself to whatever snacks you want," Remilia told them.

"Thank you very much, Remilia," Yuyuko replied.

"Happy birthday!" Youmu said cheerfully, smiling. Wow, 501 years! She looks so young, yet she's so old! That made Youmu think of another person that she hated so much right now that she could spit. Yukari is the same way...Youmu shuddered again and tried not to think too much about Yukari.

Remilia chuckled lightly. "Thank you very much, Youmu! Well, I hope you enjoy yourselves at this party!" Remilia told them. Then she walked off with Flandre to greet the other guests.

"I'm not cooking tonight, so let's eat our fill!" Youmu exclaimed.

She and Yuyuko stayed at the snack table for a while until Reimu and Marisa arrived on broomstick.

"COMING THROUGH!" Marisa called. She flew into the ballroom and a billion sparkles scattered everywhere. There were red sparks, green sparks, yellow sparks, blue sparks...every color of the rainbow was present. Marisa waved her hands around and the sparks all got into formation, forming the words "HAPPY BIRTHDAY, REMILIA SCARLET!"

"Wow," Youmu breathed, looking up at the sparks. They slowly floated down to the ground and melted away, like they were never there.

Reimu hopped off the back of Marisa's broomstick. "That was amazing! How'd you do that?" Reimu asked Marisa.

Marisa shrugged. "It was pretty easy. I just summoned some colored sparks and arranged them with a levitating spell," she replied.

"Marisa is a pretty good magician, isn't she?" Yuyuko asked Youmu.

Youmu nodded. "And a pretty good thief, too!" Youmu joked.

They both laughed, knowing that Marisa was the universal thief in Gensokyo. If you were missing an item, the first place you would go to would be Marisa's house.

The Prismriver Sisters suddenly stopped playing and Remilia made her way to the stage. She took a microphone off of a microphone stand and cleared her throat like she was about to make a speech. But then Sakuya ran up on stage and whispered something in Remilia's ear, who nodded and whispered something back to Sakuya. Sakuya ran back off stage and out the ballroom.

Remilia started her speech. "Ladies, I would like to thank you all for coming to this party. It really means a lot to me, having everyone in Gensokyo at my birthday party. You might ask, 'How is it, being 501 years old? Do you feel old?' Well, the truth is, I feel as young as the day I was born.

"I would just like to thank everyone for being my friend in Gensokyo and for excepting the Scarlet Devil Mansion's residents into the society. Well, on with the party! Enjoy!" Remilia finished.

Everyone clapped as Remilia got off stage. The Prismriver Sisters started playing Septette For The Dead Princess as everyone ran up to give Remilia a hug or a slap on the back.

"Shall we congratulate her?" Yuyuko asked Youmu.

"Sure," she replied, and so the two girls made their way up to the front of the stage, where Remilia was standing, talking to some of the residents of Gensokyo. Yuyuko and Youmu waited until she was finished, and then talked to her.

"Congratulations, Remilia! Happy birthday!" Youmu told Remilia.

Yuyuko gave Remilia a big birthday hug and Youmu couldn't help but feel jealous all of a sudden.

"Thank you so much! I hope you're enjoying the party! Thank you for coming!" Remilia replied happily. Suddenly, Sakuya and Meiling came up to her, looking very serious.

"Something is wrong inside the mansion. We're missing a vase in the main hall," Meiling reported.

Sakuya nodded. "We looked around for Marisa and asked her, but she hasn't taken the vase. We also noticed that Yukari, Ran, and Chen are all missing from the party," Sakuya added.

Youmu gasped. "Yukari?"

"Yes, Yukari. Why, did you see something happen?" Sakuya asked Youmu.

"No, but I have a feeling that Yukari might have something to do with this. I can help you two investigate, if you wish," Youmu offered.

"That would be appreciated, Youmu. Thank you," Remilia thanked her.

Youmu nodded, and then turned to Yuyuko. "You'll be okay on your own, right?" Youmu asked her.

Yuyuko nodded. "I can defend myself against Yukari if she harasses me. Besides, Marisa and Reimu are both here, so I shouldn't have anything to worry about," Yuyuko explained.

"Okay, then. Let's go," Sakuya said. Meiling and Youmu followed Sakuya down the hallway, Youmu's ghost-half following close behind. She looked around for anything suspicious, but couldn't see anything.

"In which hallway did it happen in?" Youmu asked Sakuya.

"It's up here. I'll show you," Sakuya explained.

The three girls continued walking up the hall and stopped when they reached a set of double-doors. Sakuya pulled them open and the first thing Youmu saw were the pedestals with vases on them lining the sides of the hallway.

"We're missing a vase here," Meiling said, pointing to an empty pedestal that was close to the door.

Youmu traced her finger over the empty pedestal and when she lifted her finger, there was no dust on it. Sakuya must have a lot of work to do everyday if it's this clean... Youmu thought to herself as she circled the pedestal.

Suddenly, she spotted something underneath the pedestal. It looked like a hole in the floor. She crouched down to see what it was.

"Sakuya, does the mansion have secret passages?" Youmu asked her.

"There are many secrets to this mansion that even Remilia does not know. It is so large that we don't even know how many rooms total there are. So, yes, it is quite possible that there is a secret passage underneath that pedestal," Sakuya answered.

"Well, what are we waiting for? Let's get this pedestal out of the way and see what's down there," Meiling said, pushing the pedestal out of the way. Sure enough, there was a hole the size and shape of the bottom of the pedestal.

"I'll go first," Sakuya offered, and then jumped down the hole. Meiling followed, and Youmu jumped in last.

The first thing that slapped them across the face was darkness. Except for Myon, which was emitting some light, they could not see a thing.

Youmu grabbed Myon and held her ghost-half out in front of her like a light.

"Now what?" Meiling asked.

"Well, it looks like there are three passages down here, but Youmu is the only one with a light source. So we'll all have to explore each passage together," Sakuya said, her face being the only part of her that was able to be seen in the darkness.

"We could go back up and get candles," Meiling suggested.

"Good idea. I'll be right back," Sakuya replied. Then she whipped her stopwatch out and Sakuya disappeared and came back in half a second, holding three candles.

"Thanks," Youmu told her.

"I'll take this path," Meiling announced, going over to the right path.

"I'll take this one," Sakuya called to Meiling and Youmu, heading down the middle path.

"I'll take this one, then," Youmu decided, going down the path to the left.

The candle certainly helped a lot. Myon also helped her see more of what was in front of her by floating in front of Youmu, giving off a bluish-colored glow.

Youmu kept on walking until she saw a vase on the ground. "Ah, here it is!" Youmu exclaimed, picked up the vase. Suddenly, a gap opened up inside the vase and a hand reached out and pulled her in, sucking her into the gap. Youmu struggled against the hand, yelling out cries of help.

Youmu suddenly found herself in the Scarlet Devil Mansion Battle Room. Across from her was Yukari, standing on the other side of the ring while Ran and Chen watched.

"YUKARI!" Youmu exclaimed, extremely angry. She wanted to go up to Yukari and punch her in the face, but she remembered what she had promised Yuyuko and stopped herself. She didn't want to be the one responsible for a fight. She wanted Yukari to be responsible for a fight.

"Well, well, well...look who decided to show up. Well, I guess you probably would've shown up either way, since I knew you would be the one to find the vase in the first place. Anyway, I've summoned you here for a reason," Yukari snarled. "You know how I feel about Yuyuko. But you have her right now, so I'm going to give you two options: you can try and defeat me in a battle, or you can give her up. Of course, you will most likely die trying to defeat me in a battle," Yukari chuckled.

Ran and Chen shrugged like they didn't really know what was going on.

"So, Youmu, do you want to fight and lose or just give her up? Pick quickly, or I'll pick," Yukari ordered her.

"I want to fight and win!" Youmu said quickly without thinking.

"M'kay. Good choice. This is going to be so easy. Well, I might as well show you the prize," Yukari decided. She opened up a gap with her fingers and Yuyuko fell down through it. She was all tied up and had a gag over her mouth.

"This bitch is the price. Now, let's get this battle over with," Yukari said, kicking Yuyuko out of the way.

Youmu drew her two swords quickly from her back and dashed at Yukari, who quickly opened up a gap in front of her to block the attack. Luckily, Youmu was ready for it, and went around the gap, cutting Yukari's arm open with one of her swords. She sliced and sliced, until Yukari opened up a gap beneath Youmu and had her run into a wall repeatedly. Youmu was tossed all around the room, trying to escape the gaps beneath her.

So she began flying around the room, but Yukari could also put gaps in front of her. These gaps were easy to dodge because they were usually predictable. Youmu slashed Roukanken down Yukari's back, causing blood to spill everywhere. Yukari winced a bit, but it looked like she wasn't experiencing that much pain at all while Youmu was hurting and aching all over from being tossed around like that. She knew half of herself was still human, so she had to be careful, otherwise she would become a full-ghost.

"SPELL CARD: HUNGRY KING SWORD 'TEN KINGS RETRIBUTION ON THE GAKI'!" Youmu shouted, activating her spell card. Flashes of light flew around the room and bounced off the walls, but Yukari dodged most of it easily, except for a bullet that she received to the head.

Youmu looked down at herself and noticed that she was heavily bleeding and was bruised all over the place. She didn't know if the bleeding would stop, so she had to end this fight soon, otherwise she would die of blood loss. She felt a bit light headed and couldn't hear very well.

She heard Yukari yell something incoherent in the distance, and when she turned around she was face to face with a huge train falling out of a gap.

I'm going to die, I'm going to die, I'm going to die...I'm so going to die...! Youmu thought, closing her eyes and waiting for the end to come.

"MASTEEEEEEERRRRR SSSSSPPPPPAAAAAAARRRRRRK!" Youmu suddenly heard someone yell. When she opened her eyes again, she was on the back of Marisa's broomstick and her swords were back in their sheaths. Reimu and Sakuya were both attacking Yukari while Meiling took care of Ran and Chen.

Marisa flew out of the Scarlet Devil Mansion Battle Room and flew down a hallway, turning right and then stopping at the ballroom doors. "It's 5:15 in the morning," Marisa explained. "Eirin is in here, waiting to treat your wounds. Sakuya and Meiling heard you scream and came running to get us, and so we looked around for you in that passage, but we couldn't find anything except for the vase, which is in its rightful place now.

"I heard a noise coming from the Scarlet Devil Mansion Battle Room and we all went to check it out, but we hadn't expected to see...that. Don't worry, we'll get your wounds treated and we'll have Shiki Eiki take care of Yukari somehow. As for Yuyuko...I think she needs to be with you as much as possible from now on," Marisa finished.

Marisa was right, and Eirin was waiting inside with medicine and some bandages. Youmu sat down on a table and allowed Eirin to treat her wounds, letting herself relax for once. Her pulse was beating rapidly, and Myon was floating frantically back and forth, like she was pacing.

I need to calm down, she thought as Eirin finished treating her.

"You need to get rest. LOTS of rest," Eirin ordered. "That was too intense for a human, Youmu. You may be half-ghost, but you can't forget that you're half-human too."

Youmu nodded, too exhausted to speak.

"Here, let me take you to one of the guest rooms. You look exhausted," Marisa commented, helping Youmu onto the back of her broomstick. Youmu didn't really pay much attention to the ride this time. She was so tired that her eyelids were drooping. She felt like she needed to go to sleep and just forget everything that happened.

Maybe this is a dream, Youmu thought hopefully. Then she considered it for a moment. Nah, it seems pretty real to me.

Youmu felt Marisa helping her into bed and tucking her in. She saw Marisa turn out the lamp in the room and then head toward the door, but Youmu stopped her halfway.

"Thank you, Marisa," Youmu said weakly across the room.

Marisa turned around to face Youmu, smiling. "It's nothin', Youmu. Besides, you helped find the vase and get Yukari in trouble instead of me. They would've just blamed me if they wouldn't have come up with something else," Marisa chuckled.

Youmu smiled weakly at Marisa. "You know, you're actually a really good person deep down inside, Marisa," Youmu said to her.

"Thanks. But I hope that I don't look like a good person...that would ruin my reputation!" Marisa chuckled. Then she noticed Youmu's eyelids dropping as she nodded off to sleep. "Well, good night! We'll be checking on you in the morning."
Marisa turned and walked out of the room, shutting it gently behind her.

And that's the fourth chapter.