A/N : This story was inspired by the DOCTOR WHO episode of the same name.


Prologue:

The flash of light burnt the life out of another shifter, and he was trudging away before the limp body even hit the ground. Purgatory was his penance; This was where something like him belonged, he had been so sure of that. But in the months since Dean had gotten out, the place had become darker somehow, the creatures more distasteful, even the waters more murkier. Still, this was what he deserved, and so Castiel ploughed on ahead.

"Remind me again, how are we even related?" The petulant complain, made from behind him, had him whirling around, shock and disbelief clear in his expression. This was impossible.

Yet there he was, standing in front of Castiel, all bright light and power radiating around him and setting him apart from the otherwise dreary tones of the monster infested land. He still had the appearance of the trickster though, short with honey coloured hair and broad smile.

"No need to look like you have seen a ghost brother" The arch angel grinned.

"There are no ghosts in purgatory" Castiel answered on automatic, still too stunned to process much.

"It's a figure of speech, you literal bastard" Gabriel sighed, flicking his hand dismissively, even as he glanced around with feigned interest.

"Then this is where we go when we die?" Castiel questioned, attempting to hide the terror of that possibility from his voice.

"Don't be silly kiddo, besides, I look dead to you?" Gabriel asked, as he dug up a candy bar from his pockets.

"No" Castiel replied dutifully to the rhetorical question even as a glimmer of relief washed over him, he had killed too many of his kind to entertain the idea of chance encounters with any angel.

"Exactly! Nice peach fuzz by the way" The comment, discernable even through a mouthful of oddly coloured candy made Castiel's heart clench. Those had been Dean's exact words.

"Yeah yeah, but I'm not hugging you tatty bear" Gabriel informed, eyeing him up and down with a scrunched up nose that made Castiel spare a moment to look down briefly at the dirt and filth that clung to his vessel. Purgatory wasn't much for hygiene but he supposed he must still show better respect for Jimmy's body. Then again, Jimmy was long gone; speaking of which...

"You are alive" the younger angel said bluntly, the realisation finally crashing in as he stared at the other man.

"You don't say" Gabriel mocked before rolling his eyes an adding "And before you ask, yeah I know what's been going on Godstiel"

"I - am assuming that is a reference to my temporary lack of judgement" He hedged carefully.

"Temporary lack of judgement that devastated heaven" Gabriel replied, his tone suddenly sharper. Castiel could only bow his head in shame.

"The remorse I feel for the things I have done are-" He began quietly when the other man interrupted.

"The leviathan are nasty business lil bro, there's a reason daddy locked 'em up in here" Gabriel's voice was gentler now, the step he took towards him reassuring.

"Yes, I do know that now" Castiel mumbled, still staring at his feet, unprepared to see the judgement in his old brother's gaze.

"But you are good? The fuglies all drained outta the system?" Gabriel enquired, stepping even further into the younger angel's personal space.

"Yes" Castiel answered another rhetorical question.

"Then what are you still doing here kiddo?"

Even as Gabriel spoke, a comforting hand reached out and grabbed at his elbow, causing the scene to shift around them. Purgatory faded and the disoriented and shabby angel squinted at the bright surroundings his brother had transported them to.

"Time to get back and fix things up again" Gabriel announced cheerfully as he let go.

"We - How are we out of - brother that was my -" Castiel began, still trying to reorient himself into what was a disturbingly neon coloured room, when he felt something smack his behind.

"Every time you think the word penance you get spanked bro. That's how its going to work. Capiche?" Gabriel questioned even as he turned and sauntered farther into the room.

"Yes, I capiche" Castiel responded dully, his attention still drifting through the bright colours of the room.

"Oh don't look at me like I boiled your puppies" The older man whined as he glanced back over his shoulder at a mournful younger brother.

"I don't have any-" Castiel began only to trail off when he felt something smack his ass again.

"Better. Now, how about we fix things up?" The shorter man asked, happily sinking into the nearest couch.

"I believe I am not very good at that" was the sombre answer Castiel managed, his eyes once again fixed on his shoes.

"Oh you screwed up once! Who hasn't? World is still here, you are still here, so cheer up!" The words of advice were accompanied by a rather large bar of chocolate materialising in front of Castiel.

"I do not know what I should be doing brother" Castiel confessed instead.

"For starters, eat the chocolate. We've got a long day"

- SPN - SPN - SPN -

Gabriel had made a stand against his brothers once, but he had found, he couldn't go through with it. He couldn't face Lucifer or Michael and call them out on their mistakes, and so he had run again. Running away a second time wasn't as easy though. Not when his home was in chaos and two of his brothers were locked up instead of one.

But he had told himself the dust would settle soon, things would go quiet again, and maybe he would find another few centuries of peace once that happened. As it turned out though, his luck seemed to have run out, and the dust was stirring up a sandstorm.

Raphael was being an idiot, and Castiel, bless his soul, was still a naive bastard and things went from bad to worse. It was only after his little brother declared himself God, did Gabriel feel the need to emerge again and, of course there wasn't a point going up against someone who had smote Raphael like he was nothing, so he played to his strengths and chose again to be a trickster than an arch angel.

His own ideas to get rid of the leviathan and handle his brother were stopped short when he noticed something else. A small, impossible miracle that was growing in the soul of heaven's righteous man. The recognition of what it was, was what brought two angels here now.

"That appears to be a school" Castiel commented as they appeared in front of what was indeed a high school.

"Yup, Welcome to Cliffdale high baby bro" Gabriel said with flourish, gesturing grandly towards the moderately sized building.

"And this is the place integral to your plans?" The trench coat wearing angel questioned, his head tilting slightly.

"Mmm - hmmm" Gabriel hummed in agreement, striding towards the empty building and allowing his brother a few moments of skepticism.

Castiel, for his part, continued to observe his surroundings with severe intensity as he followed without protest. Something seemed different around the place, and if he hadn't been attempting too hard to understand what could possibly be important about an American high school, he would have noticed it the moment they arrived.

"We have travelled back" He stated, blatantly surprised.

"Well done kiddo and welcome to 1997" Gabriel grinned, but said nothing else as he continued on his path. The chocolate that materialised in Castiel's path the only other token of acknowledgement.

"What happened here this year brother?" He questioned after a few minutes of silence, now increasingly curious about this grand solution the archangel had promised.

"It's a high school Cassie, lots of things happen here" Gabriel answered as he finally settled himself against a wall "But to answer your question, the apocalypse now hangs in balance here brother"

While Gabriel liked to be dramatic, he did genuinely mean the last sentence, and it seemed the younger angel had caught on to it. Almost instantly, all of Castiel's attention was back on his older sibling as he waited for an explanation.

"You know, free will, even for humans, is only an illusion Castiel. All these million lives? They are just puppet shows, going according to script. And daddy really doesn't approve when someone forgets their part"

The man was being surprisingly mellow as he started to speak, his admittance seeming slightly reluctant. But the younger angel wanted to protest, tell him, no, the Winchesters had defied it, they had won against heaven and hell, and if it wasn't for Castiel's own mistakes -

"But daddy had a weakness" Gabriel continued, snapping Castiel back to attention "See, if someone dumped the script for love, he was okay with it. That was always his lesson. Heart. love. Romance"

"Heaven chooses those who are meant to be together brother" Castiel pointed out, not understanding how romance was according to his brother unscripted.

"Ah, no. It chooses those who need to be together for the sake of a greater game. Mary and John Winchester for example" Gabriel corrected "But there have been others. Never those important in the grand scheme of things, but hundreds of humans have found their own way to their soul mates"

"People who chose their own free will" Castiel nodded in agreement.

"No Castiel. This is not about will. Its about something stronger." Gabriel chastised lightly and Castiel was suddenly reminded of all those centuries ago, when this very same archangel would address them in similar fashion, with patience and fondness. He remembered exactly why Gabriel was everyone's favorite, of why Anna had always chosen to lead her garrison to follow him…

"Tell me, in your time with all those souls, did you happen to understand what they are?" The older of the two asked, his smile softening further as he picked up on his brother's thoughts.

"What they are?" Castiel repeated, his frown deepening as he attempted to focus again.

"Grace is light. Soul though, is energy, a little bundle of force. And most of them have another - it wouldn't be appropriate to call it half, but more like a yin to their yang" Gabriel answered "They spend eternities looking for it, sometimes they return to heaven, wait it out, before choosing to move on, take another form and come back here."

He noticed his brother nodding along the lecture as he continued "But very rarely are two souls that belong together given the chance to be born at the same time or place. When it happens though, they defy all else. Such souls are the ones that return to heaven for good, never quite having to come back down here."

"The souls that have reached completion, finished their purpose" Castiel interjected.

"Yes. And then there are souls that need no other" Gabriel explained "They match the intensity of grace and are complete in and of themselves"

"I did not know that was possible" The surprise was evident even in Castiel's flat tones.

"It's rare kiddo. Incredibly rare. In fact, there has only ever been one" The archangel informed wryly and suddenly, the younger angel knew.

"Dean" He whispered quietly.

"Bingo" The older brother smiled "His destiny is set in stone. No soul mate can alter it. No romance was designated by heaven. The soul of the righteous man is an entity unique to itself, and has remained untouched throughout time"

Castiel nodded numbly. He had already known there was nothing quite like Dean, even after holding fifty thousand souls within him, there had never been a feeling that quite rivaled how holding Dean's soul had felt. The incredible warmth and the fullness that had come, even in that broken state was what had blind sided Castiel. He heard his brother chuckle dryly.

"Any angel that touched his soul was going to be lost. You had no hope" Gabriel placated even as the blue eyed man swallowed painfully. He wasn't sure what to say.

"The surprise though was when our Dean-o boy fell in love" The archangel now sounded pleased. "It's what gave me this idea" Castiel could only blink in surprise.

"I don't understand" He settled on saying, his confusion once again evident.

"You are not listening lil bro! Daddy is a big ol' sap. Plans only change when the heart eyes come out. We want to ditch the road to the apocalypse? We get Dean's priorities to change" Gabriel declared victoriously.

When Castiel continued to stand across him, blinking with cluelessness, the older sibling sighed. Sometimes, people could be so dense.

"The Winchester kiddies are moving in here next week. They'll stay a few months. This is Dean's weakest spot. The one time, he honest to dad wanted to ditch family and run. But he turned around again. Came back. dropped outta school instead, made peace...blah blah. Now, we get him to keep driving. Turn left and get out of town and its over. All plans come falling down" Gabriel still managed to sound excited and Castiel felt positively uncomfortable as he continued to stare. All of this felt like a joke.

"You asshat." The shorter angel swore after a few minutes of silence, now looking annoyed. "What part is too complicated for you? He falls in love. Something that never should have been possible. He ditches and runs. Keeps driving till destiny changes and we are all good."

Castiel nodded, the doubts still written all over him as he eyed his brother. How could it be so easy?

"It's not!" Gabriel insisted, and Castiel was starting to understand why Dean never liked him picking up on his thoughts.

"It's not easy. It's far from easy. Dean Winchester is made up of obedience to his father and loyalty to his brother. He is as stubborn about it as Michael. Shifting Dean's universe to centre around someone else is near damn impossible." Gabriel snapped, his patience finally running low.

"But if we manage to do it?" Castiel checked, mentally backtracking in an effort to not annoy the archangel further.

"Its over. Turn left onto the highway, and it's all over" Gabriel confirmed.

"Then we must attempt to do our very best to dissuade Dean from his set road" Castiel agreed immediately. Still unsure of how such simple actions could change the plans of their almighty father; but as he was, he was willing to believe his brother.

"Yeah. There's no we there champ. Its all you" Gabriel informed coolly.

"I must speak to Dean and convince him to change his course?" Castiel questioned, and the other angel swore no one frowned as much as his brother.

"No. It cannot be influenced. He must choose by himself" He corrected, attempting to hide his impatience as best as he could.

"Then what must I do?" Castiel asked, once again entirely lost.

"Go to school" Gabriel answered with a heavy sigh, even the tilted head and rapid blinking of very large blue eyes did not help. "Really kiddo, go to school"

This time the words were accompanied by the sudden appearance of stacks of books, a couple of files and even a half dozen pens right in Castiel's arms.

"I - am confused" The dark haired angel finally managed to say, attempting to look above the pile of things and at his brother.

"You wanted to fix up the world? You wanted penance? There it is. High school. Earth's own brand of hell." Gabriel waved again at the dull building behind him.

When Castiel continued to look disbelieving, the archangel added "All you need to do is go to school with him. Get him to fall in love fifteen years ahead of time"

"I think I understand" Castiel informed cautiously after a few moments. "Sam has once attempted to explain the concept of a wingman to me. Of course, Dean seemed to find it extremely hilarious because of my real wings, but I am fairy confident in my-" He felt something smack him hard from behind, almost making him drop the things he was holding.

"I ask again, how are we possibly related?" Gabriel muttered under his breath before snapping his fingers, making the books disappear. Stepping forward and placing his hands on Castiel's shoulders, he asked "Just who do you think Dean is supposed to be falling in love with?"

"Dean has never had a problem finding women interested in him" the younger sibling confirmed making his brother groan.

"Love and lust don't keep the same company lil bro." Gabriel educated him "Dean Winchester has written himself a love story already. We are only making it happen early"

Castiel could only tilt his head further and attempt to not ask questions lest he get smacked again. Gabriel too seemed to recognise that.

"Just go to school and get him to fall in love with you a second time! Think you can handle that?" He asked, his exasperation finally getting the better of him.

Blue eyes went as large as saucers as they stared unblinking at Gabriel and he could see the disbelief and the confusion swirling around; clearly the kid was going to need more help.

"Listen to me Castiel. That feeling of wanting to see Dean smile, to make him happy and keep him safe? To protect him and put him above everything else? That is love. You've been in love with Dean Winchester for a long time." Gabriel informed, and was glad when the other was smart enough to accept the truth in his words.

"The catch is, He loves you too. I dismissed it before because it was impossible but then, an angel falling for love is supposed to be equally impossible" Gabriel's voice held a note of pride that made Castiel's hands clench slightly, he did not deserve it...

"Dean cannot love me" Castiel choked out in a quiet voice, knowing that denying his own feelings for the hunter was a moot point.

"He does. He always has. Whatever happened when you touched his soul, neither of you came back the same. If there is anyone he will put ahead of his family, its you. You have to do this" Gabriel insisted before grabbing his face and pulling him down an inch.

"Brother the future down the current road is dark. You don't want to know the details, believe me. But you must not fail now." All signs of teasing was gone from the other man, and Castiel knew his brother meant the words. That scared him as much as it fueled his determination.

"H-how should I do this?" he stuttered, and Gabriel drew back with a satisfied smile.

"I don't need to tell you how to love Dean Winchester. Be yourself. Stand by him. I have faith in you Castiel"


A/N: And so, we now get to see an Angel of the Lord in high school ;) Please do leave a review!