[Welcome to the emotional roller-coaster! Before we begin, I highly suggest you go on Youtube and watch MatPat's game theory, 'Rosalina Unmasked'. The AU is based off of that whole thing (with slight alterations), so read it if you don't want to get lost by chapter 3. Unless you want to put the time into figuring it out yourself...? I wouldn't. I'm lazy.
On that note, disclaimers! All characters and concepts are property of Nintendo, and the theory was made by MatPat on the Game Theory Youtube channel. Now then.]

LET'S BEGIN!

Chapter One – A Message from Below

"A-and what about when it's raining? When I can't see the sun or the moon...?"

"My dear, I will become a star in the sky, and wait for your tears to dry..."

The cosmic princess woke with a jolt, sitting up in the tangle of purple sheets and quickly wiping at her face, feeling the dampness of tears smeared around by her tossing and turning. She blinked a few times, looking around to see that she was safely in her home, and not trapped in a misty white nothing with the ghost of someone she once knew.

'It's been a while since I've had that dream...' Rosalina's mind commented to herself. She pulled off the mangle of blankets that were beginning to make her feel trapped and swung her feet to the floor. Soft violet carpet met her toes. She certainly wouldn't be able to sleep after that dream, and there wasn't a specific schedule of sleep to follow in her home anyway, so she decided it was time to wake. Rosalina sighed and grabbed a thin silver rod with a gold star outline on the tip, standing and walking towards the door. She waved the wand in a sweeping motion, and her white nightgown began to melt away, just as swiftly being replaced with an elegant metallic blue dress. Just as the sleeves draping off of her shoulders and lavender heels formed, the princess exited her room.

Her toe met the hallway carpet with the smallest sound of a 'piff!'. It was almost unable to be heard. But the one sound caused a crowd of chubby little star-shaped entities, referred to as Lumas, to burst forth from wherever they were hiding and fly over, chanting, "Mama's up! Mama's up!"

The sight brought a large grin to 'mama's' face, instantly pulling her out of her distraught mood. "Hello my children!" Rosalina called, rubbing her nose as stardust emanating from their small bodies fell onto her face. Nevertheless, she gladly accepted three or four of them into an embrace, giggling, "How are all of you?"

"Just fine mama! But... elder Luma told us to come get you as soon as you were awake! They want to talk to you!"

"Of course." her demeanor had smoothed back out to her warm calmness, but her previous energy had seemed to spread out to the Lumas as they bounced and danced through the air above her head with excitement. "Go on and collect some starbits; so you can transform big and strong someday!"

Her suggestion caused gasping-like-sounds from the star children, and they all cheered as they darted to the direction of the kitchen. Starbits... food seemed like a good idea to the star princess, but she didn't want to keep elder Luma waiting any longer then they might have already. She kicked her feet off the ground and began to hover a few inches, the tips of her shoes just barley grazing the ground as she bounced down the stairs, onto a moving glass platform, and then to a smooth stone pathway.

Floating towards the direction of the terrace, where elder would most likely be waiting; Rosalina gazed out into the starry sky in which her home drifted. She had lived in space ever since she was small, the story as old as time of a little girl running away with a star baby into space... a reality for Rosalina. She could never complain about taking on the duty of making sure the laws of the universe were in order. It meant that she got to oversee the transformation of Lumas, a joyous time and spectacular display for her 'family' of children.

In fact, her 'castle', a space observatory, was powered by energy rich stars and rested on the back of a comet; their form of travel. Both things the product of Luma transformation. Rosalina let her drifting thoughts and wonder at the universe end with a knowing smile when she hovered over the rich grass of the terrace. At the main atrium right in between the terrace and the library foyer, the outline of elder sparkled and floated merrily on.

Halting the floating of her own for a moment to lightly bounce up a few stairs, Rosalina arrived in front of a large screen that depicted all the places in her observatory and their operating conditions. "Elder Luma?"

The ebony black Luma blinked their blue eyes in surprise before chiming, "Ah! Mother, I have something important to alert you of!"

Even the oldest of all the Lumas that had ever stayed on the observatory referred to Rosalina as a 'mother'. She always took the title with pride and responsibility, but it scared her at times. She was only human… and though toadstool heritage expanded her life expectancy immensely, she feared that one day she would pass on and the Lumas would be left wondering in sorrow, searching hopelessly for their mother… just how she had found the Luma she ran away with…

"Uh, yes? Is it urgent?" Rosalina was finding that her day had begun in a rather distant fashion. Such depressing thoughts were unbecoming on a princess.

"I would believe so," elder waved one of their stubbed arms up at the screen, and the dark blue flickered for a moment before displaying a map of their normal 100 year route through space, "Someone has been keeping a close follow on our path. I've calculated their direction, and they should intercept with the observatory within an hour or so."

"Hmm," Rosalina acknowledged his concern and watched the tiny red blip on the monitor, much smaller than anything that could bring harm to her massive station. "Go ahead and initiate precautionary measures. We can't be too careful, considering the monster a few years ago."

.!.!.!.!.!.!.

At first, it was surprising to see the red blip had actually been a red ship. But all quintessences aside, the cosmic princess was actually a bit nervous. As the small round pod neared the Observatory, it would rotate slowly and occasionally capture the bright light of a star nearby. The bright glimmer would flash straight at the observatory, causing a foreign chill to slither down Rosalina's spine. It felt eerily familiar to the chill she would feel in the fog of her dreams, and the flash would keep reminding her of a star. Her star...

Standing her ground at the opening of the garage, the space enchantress looked to the sky as the ship drifted ever closer. She didn't let a drop of fear onto her features, for the main reason of not needing to have fear. Yet. That, and her Luma family was already easily spooked. No need to make them afraid if there was nothing to be afraid of.

As the object finally came within distinguishable distance, Rosalina's heart fluttered with relief and excitement. The round, red spaceship was dotted with white spots and had a peach colored base. She could recognize that anywhere; a craft of her family's creation! Memories of the incident a few years ago flooded her mind, the red clad hero, the beast who stole the power stars... the universal reset. It could have been a fairy tale ending if not for that black hole. So joyous and yet so sad, the thought made her want to cry with happiness and scream with anger at the whole ordeal.

The feelings turned into a red-hot whir in the back of her mind, and she let the emotions go without showing any of it on her face. It seemed to be a talent of hers; inherited from her mother is she remembered correctly. But then again, she could hardly remember her at all. The ship touched down on the metallic surface of the garage, a light gust of air from the synthesized gravity causing her hair and gown to slightly flitter backwards. Ignoring the dreaded emotions, and instead focusing on the important question that had been itching at her ever since she identified the ship's origins, Rosalina cautiously approached the mushroom-shaped rocket as the main door retracted from the outer wall.

She wasn't that surprised when a Mushroom Kingdom citizen hopped out. One with bright pink spots and a matching jacket, and they held a heavy leather bag over their shoulder. The toad looked up at the cosmic princess and jumped back with a shrill yelp. "P-princess Rosalina?"

The platinum blonde nodded, neutral but still curious look in her eyes. The toad smiled with relief, quickly searching through his (or her?) bag, clumsily letting papers packed into it fall out and flutter to the ground. The toad finally ceased the action and pulled out a pale pink envelope, sealed with a stamp in the shape of a familiar gold crown...

The space princess didn't mean to be rude, but unintentionally did something to that extent when the anticipation made her snatch the letter out of the toad's stubby hand. She mumbled a half-hearted 'my apologies' and then carefully pulled off the seal... as she opened the letter, a ghostly scent of fruity perfume graced her nose, making Rosalina involuntarily relax her shoulders in remembrance.

A little girl runs up a hill, grass blowing strongly with the evening breeze. She catches up with an adult woman at the top of the hill, stopping at a tree and then plopping down with a huff at it's base. The woman joins her, gracefully seating herself and then pulling the girl into an embrace. The girl is happy with the gesture, pressing her face into the woman's light blue gown and taking in the scent of her perfume. She wanted to remember everything about her mother...

"Rosa...lina...?"

The princess was brought out of her memory, lowering the pink stationary and pulling it out of smelling distance. She figured the toad was just as curious as her to what the message said, so the princess of the cosmos read aloud,

"To her Highness Princess Rosalina of far beyond the stars,
We are eternally grateful to you for your aid in rescuing Princess Toadstool during the time of the star festival. To express our gratitude, the Princess is hosting a ball at the castle in your honor. By calculating the speed at which your comet was traveling..."

"Calculated? Does the mushroom kingdom have the technology for that yet?" Rosalina paused her reading to question the toad. It's face seemed to light up, and it merrily exclaimed, "Ever since Bowser was arrested your brightness! Immediately after Princess Peach and Mario returned, she began the construction of space observatories!"

Rosalina smiled in delighted surprise. The mushroom kingdom had advanced exponentially in astronomy, thanks to her! But something else the toad said caused her to further inquire, "The monster? Bowser, was he put in prison?"

"Absolutely! It's all safe now Princess!" The toad pressed the tips of it's stubby fingers together, asking in a sheepish voice, "How does the letter end?"

"Oh! Of course, I should finish that..." The princess exclaimed in realization.

"By calculating the speed at which your comet was traveling, we estimate this letter will arrive a week before the ball. It would overjoy us if you could attend personally, and accept a gift we have prepared.
In respected recognition,
-Lord Toadsworth"

A ball at the mushroom kingdom, especially for her. The cosmic princess held the letter lightly against her chest, taking in its peach scent once more and mentally contemplating if she could attend. After taking on the responsibility of the Lumas, she had learned the truth about universal rebirths and thought it would be best if she didn't let people from two different sets of time interact. Was she herself, manipulator of time, exempt from that rule? She badly wanted to see old faces once more, almost to the point of making her chest ache with yearning. Yet she knew the Lumas needed her to care for and watch over them... leaving for a party would be neglectful.

Taking the observatory and the Lumas on it with her, would throw off the comet's cycle. And on a further note the star festival... but to see her family... an exception could be made, she was sure.

"I... I think I'll accept the offer. It might take a while to redirect the comet's path, but you can expect me there... I wouldn't miss it for the world."

[*rubs hands* and it begins! I have no idea how long this story will go for after 3 chapters... so leave a review, and suggestions are much appreciated!]