"Why?"
Noire asked the simple question as the four CPUs approached the entrance of the strange dungeon that had appeared out of nowhere. Neptune had asked the others to explore it with her.
"Because it'll be fun! Maybe we'll find some new, strong monster!" Neptune said enthusiastically.
"I don't know if that's necessarily a good thing." Blanc said as they walked into the gaping maw of the dungeon.
It was very dark, so Vert took out some flashlights she had taken just in case. The dungeon seemed empty of monsters; empty of anything in general. That is, except for sharp rocks that seemed to protrude from every wall, the floor, and the ceiling. The rocks nicked at them, tearing their clothes as they went.
"Dammit, I liked this outfit!" Noire complained.
"It looks like all your others." Vert noted, her top half torn up enough that her lacy green bra was visible. They continued onward, Neptune humming to herself, before Noire cleared her throat.
"Neptune…" she said hesitantly, and Neptune turned to find a slightly blushing Noire, who outfit had been so shredded that it was hanging in scraps from her body, exposing her underwear. "Your clothes…" Neptune looked down to see that her own outfit had been completely destroyed, leaving her fully in her underwear.
"Oh! Well, it should be fine. If anything, it'll help me move around faster if we find some monsters!" she said, trying to stay cool, even though she felt her face burning a bit. "Besides, you guys are also…" Noire went wide-eyed, and looked down, along with the others, to see their state of dress. Noire squealed and covered herself.
"Th-that's not-!" Noire started as she looked back up at Neptune, but stopped herself, her expression turning into one of fear as her eyes moved behind Neptune. Neptune slowly turned, and gasped.
Where there had been nothing but cave less than a minute before now existed...something. It looked like a monster. It consisted of a giant eyeball, surrounded by dark tentacles that looked almost like vines, covered in dark tentacles that impossibly wrapped around each other infinitely. It was almost mesmerizing, but what shook Neptune out of whatever trance she was falling into was the realization that the tendrils were holding two girls. They were naked, one was short, with brown and pink hair that was almost split directly down the middle, and the other was tanned with green hair. They were unconscious.
"Wh-what are you?!" Noire asked, trying to sound forceful as she took a stance, but her shaky voice gave her away.
"I apologize."
Everyone froze as a deep, almost soothing masculine voice sounded in their heads. It was obviously coming from the creature, which was talking telepathically.
"You are just so much fun to mess with." it said.
"Who are they?" Blanc asked, gesturing to the two girls. Suddenly, they vanished, like they were never to begin with.
"Don't worry about them." the voice said. "They aren't from your reality anyway."
"Um, what?" Noire asked. "Like, a different dimension?"
"No, an entirely differently reality." it said, and the CPUs stared dumbfounded at it, unsure what it meant. "You wouldn't be able to understand."
"What are you?" Noire asked again. Laughter sounded in their heads.
"You wouldn't be able to truly fathom what I have been doing." it said. "To put it simply, I have been travelling across several timelines to try out different...scenarios...and have fun with you all." The CPUs didn't really have anything to say to that, so it continued. "Despite what you may believe, or how you view existence, yes, there are different dimensions, but there are also different timelines across those dimensions, a near infinite amount, in fact. I have used these timelines to experiment. In one, I dropped a book, and in another, I created a plant, and on and on." The being paused. "Of course, yours isn't the only reality I've been messing with, which is an entire new level that you can't comprehend. I've created a mansion, turned an innocent girl into a sex-crazed maniac, put the idea of a fun game into a chef's head, and more."
"Okay, okay, stop." Neptune said suddenly. "Timelines, dimensions, realities...isn't this stuff usually what you say in the final battle, after hinting to it throughout the entire story until it all gets revealed, and you're like 'Oh! That makes sense now!'"" she asked. "Plus, you're not good at monologues." Suddenly, the being's eye was right in front of her. She yelped and leapt back.
"You…" it said, examining her. "You are aware of higher planes."
"W-well…"
"Interesting." he said, cutting her off. "I have previously kept myself hidden, as I didn't need to interfere directly. But, for this next set of scenarios, I'm afraid I need to."
"Can you just stop-" Neptune started, but she suddenly vanished before the CPUs' eyes, her underwear falling to the ground.
"N-Neptune!" Noire exclaimed, and glared at the being as she prepared to transform, but she too vanished, her underwear joining Neptune's.
"What are you doing with them?" Blanc asked.
"She was right. I am bad at monologues." it said, ignoring her. "Either way, I'm done with you, and I'm ready to begin, so...have fun." The other two CPUs' underwear joined the pile as they too vanished. The being simply stared at the pile.
"I really must get better if I want to do it well." it said, before it vanished as well.