Sky stepped into the blue box and soon wonderment filled his expression as he finally was able to fully take a look at the control room.
“She’s beautiful,” he then said.
“Yeah, she really is, and we've both been through so much together, she’s one of those few constants I had over all those many years,” The Doctor said.
“Wow, that is really de-ooh button!” Sky said as he caught sight of a big red button.
“No! Don’t touch that!” The Doctor yelled about to pounce towards Sky but Derpy beat him to it as she flew and stopped Sky’s hoof.
“Um, Sky, I wouldn’t do that,” Derpy said.
“Why not?” Sky asked.
“The last time that button was pushed… well, let’s just say that a pony was sent into exile for 1000 years,” The Doctor said.
Sky thought for a moment and the lightbulb went off, “Oh, so you mean-”
“Yep, part of all that mess was our fault, we stopped her from taking over the Equestria, but the damage had already been done,” The Doctor replied.
“Wow, that’s an interesting bit of trivia,” Sky said after a moment of silence.
“If only you knew everything I’ve seen, Sky, it’d rock you off your knockers,” The Doctor said.
“Knockers?” Sky asked, not knowing the slang term.
“Nothing, slip of the tongue,” The Doctor quickly said while Derpy grinned, “Oh shush, you got them as well as every other mare.”
Derpy poked her tongue at the Doctor, which cause the Doctor to chuckle a bit.
“Where have you gone most recently?” Sky said as he took a look at one of the monitors showing the area around the Tardis.
“We visited Star Swirl the Bearded, it was fun being at such a different time than today,” Derpy said.
“It was quite a different time, and it means you’ll be able to understand Princess Luna in the times she uses that old-timey lingo of hers,” The Doctor said.
Sky nodded and looked as Miss Cheerilee walked through the area in front of the Tardis and appeared on the monitors, “Have you ever visited anytime of the recent past, like Princess Luna’s return or anything like that?”
The Doctor shook his head, “No, one cannot visit a time they existed in, it would cause all sorts of timey-wimey disruptions, and should one change the wrong moment in time, it would cause that time-line to be destroyed.”
“Seems extreme,” Sky commented.
“All in the name of keeping timelines clean and orderly, you can’t have some random fella waltzing into time and space acting like he owns the whole bloody space,” The Doctor replied.
“Reminds me of a certain pony,” Derpy joked causing herself and Sky to laugh.
“Oh shush you two, I haven’t reached the age of 1200 without earning the right to be clever about it all,” The Doctor laughed.
Sky looked around more as he wondered about just what this old machine and the Doctor had gone through before that point and looked towards one of the hallways, “What’s down that way?”
“The pool, despite the changes this old girl has gone though, she has been adamant on keeping that pool,” The Doctor replied, “It’s a nice pool and all but why the pool? I’ve never gotten an answer out of her though.”
Hours later, Sky had basically finished the tour but stayed anyways just to keep looking at the console room. In a room much like a kitchen, The Doctor and Derpy spoke about the changeling, “I told you he wouldn't touch anything,” Derpy said.
“Except for that close call with the button, but other than that he has been quite a good guest,” The Doctor replied. He then noticed Derpy about to ask a question so he answered, “I know what you are gonna ask and we are not taking him with us, he’s needed here.”
“Oh come on, wouldn’t it be nice to have somepony else to share in our adventures?” Derpy rebutted.
“I’m perfectly fine with just the two of us, thank you very much, and he’s pretty young besides,” The Doctor replied.
“Never stopped you before,” Derpy replied with a smirk.
“Oh come off it,” The Doctor replied with a smile, “He’s not coming and that’s final.”
“Oh fine then,” Derpy replied sourly.
The Doctor and Derpy re-entered the console room and bid Sky goodbye. Once Sky was outside he saw a pink-colored wave in the sky, and black spots within that wave. He waved it off in his mind as nothing.
One day later, as Sky was reading the newspaper, he read an article about the invasion of Canterlot. “Oh this is not good,” Sky said to himself. He needed to make especially sure to not be caught now. He resolved to only shapeshift in that secondary home of his and to visit it only once a month.
A year later, Sky is in Twilight’s castle. Nothing significant happened since the invasion except for the various happenings that were becoming quite often in Ponyville. Why is Sky in Twilight’s castle you may ask? During the whole Tirek episode, Sky was in that secondary home of his and thus was unknowing of Tirek having found Ponyville until he heard the explosion that destroyed Golden Oak Library. He left that hole of a secondary home and Tirek found him. After sucking the magic from Sky, Tirek left to try to get Twilight. Sky was left near the hole into his secondary home without his magic and thus without his disguise. He was found soon after the ponies got their magic while Sky was still weak despite having his magic back. He wasn't sure why he took longer to recover from that, probably something mental. Anyways, He was found and, after some protests, was sent to the dungeon in the castle without Twilight’s knowledge. He had been in there for about a fortnight before the Princess found out he was in there (Probably due to her avoiding the castle until her friends spiced up the place).
So, as Sky stood in presence of the Princess in his cell, he nervously thought about what was gonna happen to him and his family.
What if they punish them for raising me? What if they find out that mom is a changeling?
It didn’t help that he was forced to be in his natural form by some spell in the dungeon.
Sky’s thinking was interrupted by Princess Twilight suddenly appearing surprising him. She then asked., “How long have you lived among us?”
The sudden question confused Sky, this was totally different from what he thought would happen. He expected a lot more hostility in her voice, he wondered if she was hiding it. Seeing no reason to lie now, he answered, “All my life, so around 21 years.”
“21 years? How have you escaped detection all this time?” Twilight asked surprised.
“Luck is a big factor, I guess it finally ran out for me,” Sky answered again.
“Alright then, now why have you lived among us so long even after Chrysalis’s invasion? Were you a part of the invasion? And do you follow Chrysalis’s demands?” Twilight continued asking.
Sky answered, “I always lived among ponies, I simply saw myself as just a unique pony. I was not a part of the invasion and I don’t follow that Queen’s orders. Changelings aren't a hive mind.”
Over the next few hours, Princess Twilight began to feel more and more sympathetic about the changeling in the cell. She asked one final question, “Do you feed on other ponies?”
“All the time, I’ve learned how to collect the background emission of various emotions by other ponies and of course I’ve learned to feed on emotions other than love. It doesn't hurt the pony being fed off except for a small drop in energy,” Sky answered truthfully.
“Thank you, I will be making an inquiry to Princess Celestia for a decision on what to do with you,” Twilight said ending the interrogation before leaving the room. “Spike, I need to send a letter to Princess Celestia.”
A few hours later, Twilight returned to Sky. “Sky Sprinter, Princess Celestia and I have agreed that having you rot in this dungeon would be a terrible thing to do to you. So we have agreed on a probationary term for you. I will watch you and keep you out of trouble. If you don’t cause anything to give us reason that you are a menace to society then you will be released. However, you must live here in the castle with me and Spike so that we may closely keep watch on you.”
Sky was at first elated at the fact that he’d finally be out of that dungeon, sure it wasn't too bad but it was still a dungeon. When he heard about the probationary term he understood why but then the fact that he’d have to move out of his house got to him. “I-I can’t return to my home?”
“Oh you can visit all you want, but you must live in the castle until we deem you worthy of it,” Twilight answered, "You must always be watched by at least one member of the Elements of Harmony."
It can’t last that long, right? It can’t be too bad, correct?