Sonic maybe should've been more panicked waking up in a mysterious facility, in a different dimension, with people claiming to have access to time travel... Then again, he was Sonic the Hedgehog, hero of Mobius, the guy who had beaten Shadow, Metal Overlord, went to two different story book worlds, and fought actual gods.

So yea, Sonic was pretty calm... And had even been introduced to some pretty good books, the Illiad had grabbed his attention pretty quickly. It was a bit slow, but enjoyable read. But it hadn't distracted him enough to not notice when the door opened, his ears twitching. He turned to greet whoever had come in.

Mashu Kyrielight was nervous, when Da Vinci and Romani had explained the situation to her she was both nervous and excited, a visitor from another dimension? It sounded like a fantasy book! But she had seen the security camera's, this was very real... and she was being asked to give them a tour of Chaldea! But it did mean she'd not be visiting the first Singularity with the other master candidates...

She shook her head and opened the door to meet her latest Senpai, eager to ask him stories about his own world and...

King.

That was all that went through her head, even as he met her gaze with a casual smile, and replied to his words, her entire being screamed that this creature was both familiar and totally alien. He was a king, yet he wasn't.

For Mashu Kyrielight, Sonic the Hedgehog would become many things, but for now he was just her senpai.

"So your names Mashu Kyrielight huh? Nice to meet you, I'm Sonic the Hedgehog!". Sonic offered his hand to the pink haired girl, who shyly nodded but accepted the handshake.

"I-it's nice to meet you, Senpai!". Mash smiled back, she seemed strangely shaken by something but what Sonic was unsure. "I'm here to give you a tour of Chaldea, are you ready to depart?".

"A tour huh? Sure! Small rooms like this are not my place, I prefer somewhere with lots of space to run ya know?". He smirked and quickly rushed outside of the now opened door, Mash hurrying to follow.

"Please don't run to far Senpai! While Chaldea has been informed of your existence most will be nervous and its a very important day today! So we can't distract the Master Candidates!". Mashu stated, with Sonic turning to her confused.

"Master Candidates? I sure hope you don't mean this place supports slavery". Sonic asked casually, he was teasing but yet a part of him was still worried. Rule number one of visiting another world, don't expect it to have the same rules yours does.

"N-no! Slavery is illegal, a master candidate is someone with the potential to form a contract with a Servant, a Heroic Spirit!". She explained, but when Sonic just kept looking at her confused, she explained more. "A Servant is a container for a piece of a Heroic Spirit, someone who's great deeds in life have them recorded into the Throne of Heroes. They usually can't be summoned easily, but thanks to Chaldea mages can summon them".

"Huh, so more magic ghosts, you could've just started with that". Sonic wasn't exactly fond of all the terms they used, you don't just name something a Servant and yourself the Master if you were a good person. The fact it was giving him flashbacks to a previous adventure weren't helping...

"Its a bit more complicated then that... But I suppose you are correct Senpai. But please don't go calling Servants magic ghosts to everyone, it could be taken the wrong way". Mashu tried informing Sonic, who just grinned and looked around Chaldea.

There weren't many facility members, most of them being distracted by the Rayshift soon to commence. But there was one currently walking the halls and approaching the duo.

"Ah, there you are Mashu... and I see you have our visitor with you! Hearing it over the radio was one thing, but seeing it in person is another!". The man stated, giving Sonic and Mashu a smile... And alarm bells were ringing in Sonic's head, green suit, green top hat, and a frankly crazy hair style. He seemed a bit odd but kind, so why was everyone of Sonic's animal instincts screaming fight or flight?

"Nice to meet ya! Sonic's the name, speed is my game!". Sonic greeted casually, best to remain calm. If this guy was trouble he'd deal with him, but it could just be his instincts going off at the wrong thing.

"A pleasure, Lev Lainur, a professor here at Chaldea. However I am not here for pleasantries alone, Mashu is being called for the Rayshift testing". Lev explained, causing Mashu to frown.

"Doctor Romani and Da Vinci said I'd be skipping the Rayshift to keep an eye on Sonic...". She trailed off, unsure what to do. If the Director was asking for her, her authority was above Roman and Da Vinci...

"I see... I'll have to inform Director Olga then, while its a bit disheartening to hear you won't be there for the Rayshift, I'm sure Olga will understand once I explain the situation to her". Lev said, giving Mashu a kind smile.

"Ah chill, its not that bad is it? Your missing one person and from what I've heard you've got like, 50!". Sonic interjected, fighting down the urge to spin dash Lev. Something was off, he didn't know what but something here was triggering his danger sense.

"48 Master candidates actually, but you were close. But I believe its best I go inform Olga of whats going on, please enjoy the rest of your tour, may I recommend laboratory? The technology and mystic codes held within are truly a sight to see". Lev gave one last smile before walking off to perform his duty.

"Laboratory huh? Sounds neat, but I was more thinking the kitchen! I have no idea when I last ate, but I'm starving!". Sonic had no intention of going anywhere Lev recommended, maybe later but right now he suspected if he walked into the lab, he'd be strapped to a table faster then you could say 'Chili dog'.

"Ah! You must be very hungry Senpai! Kitchen first!". Mashu agreed, trying to hide her own discomfort at visiting the lab. She hadn't eaten much ether, it would be safer to Rayshift on an empty stomach.

The young girl started leading Sonic to the cafeteria, there was nobody running it currently but it wasn't to difficult to grab some bread and sandwich supplies. Sitting down at a table, the two prepared their own sandwich.

"So Senpai, whats your world like?". Mashu asked excited, eager to learn about the hedgehog's own world.

"Well its like any place really, although the names can change depending on who you ask. Humans insist on calling it Earth, but mobians like me call it Mobius, like why would you guys name your planet after dirt?". Sonic asked while munching down on a sandwich, it was no chili dog but it served as a good lunch.

"I don't know who named Earth earth, but it does sound kind of silly when you say it like that. What about where you come from Senpai?". Mashu pulled out a notepad and pen, gifted to her by Da Vinci for any important notes she felt the need to take.

"Me? I live in Green Hill zone, big open place with lots of areas to run, loop da loops, and fuzzy animals everywhere! Sadly, Eggbutt's constantly trying to take it over, but yours truly deals with him". Sonic smirked, grabbing a second sandwich.

"Loop da loops? Your home has actual loop da loops? Like in a game? And who's... Eggbutt?". She asked, but was confused when Sonic started laughing.

"Hahaha! Oh man you actually, nobody ever uses the nicknames so seriously! Eggman's a crazy scientist back home, classic dreams of taking over the world and stuff. Not a single person doesn't know him back home, he's not been doing extreme things lately and been more focused on taking me down, but sometimes he has went to some pretty extreme measures like blowing up half the moon". Sonic stated it so casually... forgetting he was dealing with another world.

"D-DESTROY HALF THE MOON! S-senpai thats impossible, the level of power needed hasn't been created yet! Even if your world has more advanced technology, it just isn't possible to destroy half the moon!". Mashu couldn't believe her ears, notepad long forgotten.

"I mean maybe here its not, but back home there's this old satellite called the ARK, and it houses a weapon called the Eclipse Canon. It has the power to shatter a planet in two at full power, but Eggman in the past used it to destroy half the moon while threatening the people of Mobius to give him control or he'd fire the Eclipse canon at earth. But me and my friends managed to stop him". Sonic explained, causing Mashu to become starry eyed.

"Thats incredible Senpai! Your a real hero!". Mashu exclaimed and would continue asking more questions of locations, history and events in Sonic's world. But she would notice something mentioned a lot but never with an explanation what they were.

"Uhm Senpai, you keep mentioning these things called 'Chaos Emeralds', but what exactly is a Chaos Emerald?". She asked, and just as Sonic was about to begin his explanation...

BOOM! BOOM! BOOM!

Multiple loud explosions would echo around the building, the floor shaking and throwing the sandwich supplies everywhere. Pieces of the ceiling started to fall, Sonic didn't even hesitate to act, grabbing Mashu and quickly zooming out of the room.

"S-senpai! The Rayshift! We need to go to the Rayshift chamber! The Director!". Mashu while disoriented and confused from the speed they were going at, she needed to check on the Director and Master Candidates! Sonic gave a nod and she started giving him directions.

It only took them around 15 seconds to arrive at the Rayshift chamber, Sonic put Mashu down and began running around the chamber, desperately trying to find anyone still alive. He put out fires where he could but anyone he found was in a... He shook his head and looked to Mashu, who was slowly moving rubble away, her limbs glowing with the tell tale signs of Reinforcement magecraft.

"S-senpai! I-i don't know, the candidates are trapped in the coffins and s-some are...!". Mashu couldn't finish her sentence, her cheeks turning green. "T-The coffins s-should keep them stable! We need to find anyone outside the coffins and-!". She was cut off by the radio.

"Generator operation stopped. Power level critical. Switch to backup generator, error. Please make the switch manually. The containment wall will close in 50 seconds. Those who remain in central area, evacuate immediately".

Sonic ignored the announcement and kept checking for anyone still alive, Mashu joined him but it was clear she was starting tp panic.

"System switching to the final phase of Rayshift. Coordinates, AD 2004, January 30th. Fuyuki, Japan. Laplace's shifting protection was established. Singularity's additional factor slot is secured. Unsummon program set, please set final adjustments".

"S-senpai! We need to get out!". Mashu cried, but it was to late, the containment walls had fallen, they were trapped in.

Sonic looked about for a way to escape, there wasn't enough space to build up the speed required to break out!

"Warning all observation staff. Chaldea's state has changed. Now rewriting Shiva's near-future prediction data. Unable to detect the existence of mankind for 100 years shortly of Earth. Unable to confirm human survivors, unable to guarantee mankind's future".

"SENPAI! C-chaldea turned red! T-this is bad! This is really bad!". Mashu's breath was coming out to fast, Sonic recognized the sign of an upcoming panic attack.

"Mashu! Calm down, calm down, we can fix this! Focus on me, ignore the announcements, focus on me!". Sonic spoke, distracting Mashu and having her focus on him. He had no idea what was going on, but he could fix it once she was calmed down.

"Central Area, sealed. One hundred eighty seconds till internal containment procedure".

"S-senpai, I-i don't know whats going on". Mashu tried keeping her breathing calm but, it was hard! S-she couldn't do this, she was scared!

But... One thing happened that calmed her down.

"Coffin Vitals: Master baseline not reached. Rayshift requirement not met. Searching for qualifying Master Candidates... Found. Unidentified Candidate reset as Master. Unsummon program, start. Spiritron conversion, start".

"S-senpai...". Mashu stared at the gloved hand holding her own, and looked at the confident grin of Sonic the Hedgehog.

"Hey, it'll be alright... You know why? Because I'm here, and Sonic the Hedgehog never leaves a friend behind!". Those simple words... A warm feeling went through Mashu's body, her fear fading away.

"Rayshift starting in 3... 2... 1... All procedures clear. First order, commencing operation".

For Mashu and Sonic, the world disappeared in a flash of light.

THE BUTTERFLY HAS FLAPPED ITS WINGS! I REPEAT THE BUTTERFLY HAS FLAPPED ITS WINGS! Consequences are already appearing from Sonic showing up in Chaldea!

Now, before this ends I have a question for everyone. Based on compatability, what Servants do you think fit with Sonic?

Some like the Round Table are automatically fitting because Sonic IS King Arthur, and others like Atalanta/Achilles fit because of the fastest thing.
But who else fits and who do you guys recommend? I'm not exactly sure on Servants for Sonic, so recommendations are good. Ideas for how they'll interact is also appreciated.