Disclaimer: I do not own Persona 3—or any version of the Persona series, really. I just own this rather shameless piece of work.

Other Notes: Starting this fanfic has made me finally get a move on to learning the full plot of Persona 4. I wanted to eventually finish playing it myself (I'm only at the beginning of Rise's dungeon…), but I think I've finally come to accept that I don't have the same time to dedicate to playing it through as before. Thankfully, YouTube exists. With Golden videos, no less.

Ah, this should also clue you in to the fact that this OC SI has only the same knowledge I did when I decided to write this story. I've read some stuff on the wiki from the later games, but I think I've managed to avoid spoiling myself majorly until now (I think). We'll see how that affects things as we continue on, but I guess I just wanted to get this out there so people who know the later games don't wonder things like "This was explained in 4, so why doesn't she know?"

Symbiosis

Chapter Three

In the end, Minato did go to live with relatives, but in a very loose sense. Long story short, he more or less lived an existence of being passed from relative to relative like a hot potato.

"Other", as she supposed she was dubbed now, watched as this occurred from within Minato's mind. She could understand some of them, given that they had their own families or unstable incomes that could make living difficult even without having the six-year-old orphan on the side. But she could not help frowning and furiously ranting about some of his more selfish relatives, who clearly had the means and ability to support Minato living with them but simply could not be bothered.

The rants were mostly for herself, she admitted, to vent out her feelings of uselessness. But they were also partially for Minato. She could not quite shield her thoughts from him while he was awake yet and he was uncannily good at knowing when she was upset, so she made do by trying to make him feel better about basically being set aside. If coming up with immature insults about this distant uncle or that spoiled aunt did the trick, she gladly did so.

Most of her time was spent like this, simply watching as Minato's life moved on and chatting with him in hopes of making him feel less alone. She kept an eye out for lingering signs of trauma, too, soothing him through it as best as she could. The worst had to be his aversion to cars and being in them. It was… a work in progress.

It also became apparent that he was truly a quiet child, though she worried off and on that he was being too reclusive. She'd had a nephew who was similarly quiet and preferred to keep to himself in his formative years, but even then he'd had moments of high energy where he craved social interaction.

Sometimes, she took cues from the various adults in his life and shrugged his behavior off—she was no child psychologist or what-have-you—but sometimes her paranoia and worry made her simply unable to trust them.

During those times, she always checked in on his status.

"Reading again, Minato?" she asked, trying to send him the feeling of a pat on his head. She'd been doing that more frequently now, trying to find the limit of what she could do from within his mind. Sending him phantom sensations was odd, but one of the easiest. It often helped to comfort him, too, since he rarely got physical attention from his other family members.

Yep, he answered, thinking directly at her instead of replying aloud as he used to.

(After living with a couple of relatives, she realized rather belatedly that he tended to talk to her out loud. Though he sometimes tried to quiet his voice when around others, he always spoke freely when he thought he was alone. One aunt walked in on him in the middle of one of their conversations and had looked so worried that Other decided to put a stop to it, telling Minato to talk with her in his head only.)

(He had been confused, but he thankfully agreed, trusting her judgment.)

"Not gonna go out and play with your cousins?" she mused. "These ones were much nicer than the other ones at the last house. I'm sure they won't leave you alone."

They were innocently insensitive, as children were wont to be, asking Minato about his parents and the crash. But at least they didn't look at him as if he were some alien intruding on their lives or ignored him out of petty jealousy for holding their parents' attentions while he adjusted.

She had to fight to keep her irritation at bay just remembering. Damn brats.

No thanks, he replied, thankfully unaware of her ire and idly flipping a page. She barely paid attention to the artwork of what was supposedly a depiction of the phoenix's fiery rebirth. I don't like hanging out with them all a lot. Too crowded.

Distantly, she was reminded of a certain other character that disliked "crowding"—amongst many, many other things—and shuddered at the idea of being stuck in his mind. "Okay. Just making sure."

Besides, he added, I have you, so I'm not alone anyway.

Frowning, she shot a wary glance over her shoulder where Death's door loomed, ever present even while dormant. She still didn't know what would happen to her when Death began to awaken. Pharos had been fairly… harmless even in his first appearance as the Mysterious Boy, if a tad creepy, but she also knew that his Thanatos form would have a sort of psychotic break during Orpheus's first summoning.

She wanted to be optimistic in her own continued survival, but she knew from experience that the Persona series were games where everything could change at the drop of a hat. And often quite brutally.

"Not that I'm not flattered, kiddo," she began, "but try not to depend on me too much, yeah? I might not always be here."

Outside, she saw Minato's hand still in its action of flipping another page. When his mind began to flicker, full of volatile and mixed emotions, she cursed. Too soon! Too soon!

You're not gonna leave, are you? Minato asked, a slow dawning terror encroaching upon his mindscape like a heavy black fog. Please don't leave! First Mom and Dad—I don't wanna lose you, too!

"Minato—"

He was frozen, staring down at the page in his mute horror. Before she could get another word in edgewise, she was overcome by a veritable tidal wave of his fear—the fear of being alone—and grief all at once.

Did you want to go out and play? I can do that! I—I don't mind, just don't… he sobbed. Please don't leave…

Even as the wave enveloped her, all she could feel was guilt. She had just been thinking for his benefit of not getting too dependent on her in case she disappeared one day. She didn't think he would be so scared of losing her, who was at most just an imaginary friend as far as he knew. But it seemed he cared more than she had believed.

The thought was both heartwarming and distressing.

While she was glad to know that her presence wasn't a burden or an annoyance to him so far, she wondered what it meant for his psyche to be so attached to someone in his head.

Minato was essentially settled into his odd life when he turned eight, celebrating his birthday quietly with the lone uncle he was currently living with and spending the rest of the day alone. Of course, in reality he was with her, his proclaimed Other, celebrating "their" birthday by doing what they enjoyed: reading.

It was just as he got to a simplified version of the tale of Kaguya that she finally asked him why he called her his Other.

There was a moment of plain confusion as he registered her question.

Then, he replied, Because you're my Other.

It was said, or thought, so simply. As if it answered everything rather than nothing.

"What do you mean by that?" she asked.

Well, said Minato. You're always there. In my head. I asked a kid in my class once if he had something else in his head, too, and he said no. So did a whole bunch of other kids. So I thought I had something special. Another me. So, "Other".

In a way, he probably wasn't entirely wrong. If she had been meant to be reborn as him only to be caught up in his soul and his "potential", then she would have technically been him. A literal "Other Minato".

She hummed, understanding. "I see."

Minato gave a responding hum before returning to his reading. He was only at the beginning, when the old bamboo cutter found the infant Kaguya in the shining stalk.

After a moment of debate, she decided to ask something else.

"…Say, Minato, would it be okay if I used a different name? Not that I mind being called 'Other', but it's kind of weird sometimes." It was a bit dehumanizing, rather, not that she'd tell him aloud for fear of making him feel bad.

Minato paused again. Then, he sat up from his position of reading on his stomach on the floor.

Okay, he agreed readily. What do you wanna be called?

She honestly had no clue.

She had been an aspiring writer in her past life, but if there was one thing she would likely never forget about that, it would be her inability to name things in a timely manner. Naming, for her, was an absolute chore.

"Um… Why don't you help me?" she suggested. If she sounded a little desperate, she firmly ignored it. Minato was a smart kid; he could definitely help her! "What do you think my name should be?"

He would be the only one to know it and use it, anyway. She had a feeling she would be stuck in his head for a long time, sudden death-by-"Thanatos" scenarios aside.

She watched as Minato eyed the little mythology book an aunt got him for his birthday last year, pulling it towards him to flip through the contents. He was quiet for a long time, turning page after page. But, just as she began losing faith and fearing that she would end up with a random, overly complicated name, he suggested something that made her blink.

"Did you say 'Tamago'?" she asked, perplexed. All that perusing through the myths and he chose to name her after his breakfast?

Minato snickered. No! I said "Tamamo". Like Tamamo-no-Mae!

"Oh." She recognized that name. It was a myth she remembered a little obscurely, or so her memories told her. The only reason she honestly recalled it was because the character in the myth appeared as the identity of a Servant in a certain TYPE-MOON game.

…Yeah, she could live with that name. It was easy to remember and wasn't half-bad.

"Sure," she agreed, smiling. "From now on, I am Tamamo."

Minato laughed again. Nice to meet you, Tamamo!

She chuckled. "Nice to meet you, Minato. And thank you. For naming me."

His mindscape lightened in response, pleased to have helped.

(Much later, she would remember the full version of the myth and wonder why he decided to name her after one of Japan's three vilest youkai. This would also make her realize that Minato, for all his introverted nature, was a bit of a rascal when he wanted to be.)

The days faded into weeks into months as Minato's life moved steadily onwards. He was still shuffled from family to family, but over time it seemed to become more of an annoying inconvenience to him than anything else. This worried Tamamo, as many things tended to do these days, but he insisted on reassuring her that he was fine with it, never holding it against his family members for being unable to settle him somewhere. He was indifferent to the matter and took it all in stride.

Unable to argue or do much of anything else, Tamamo let it slide and instead focused on helping him behind the scenes. Being trapped in his head gave her plenty of time to learn what she could do, after all, so she used the majority of her time to practice when not watching Minato's life or chatting with him.

And, as it turned out, despite the fact that she had no body of her own, there were some things she could do from within his mind. Perhaps she had the universe to thank for that, as much of the Persona series relied on the somewhat abstract power of the mind and soul.

The first of the two main "abilities" she learned was her ability to influence certain things in Minato's mind, like his dreams when he slept. She had finally taken the leap into the deeper parts of his mind when a particularly bad nightmare disrupted his mindscape while he was asleep. Though she took care not to be drawn in to the dream itself, she carefully tugged and blocked the images that plagued him until he settled.

It was a rather easy task, especially when she got to learning how to set mental constructs. It also gave her something to do while he slept and so she safeguarded his mind as best she could, glad to be of some use.

That said, mental constructs were what she experimented with next. Given that she was in a mindscape, her automatic thought was of utilizing the power of imagination: to create something out of virtually nothing. This was much more difficult a task than it sounded, as it required concentration on her part to actually form something fully and correctly. The cartoons always made it look easy, just poof! Instant item. Not for her, though. There were a lot of failures of items half-created. If she hadn't erased them all, she would probably have her own little rubble pile. However, once she got it down once, it became much easier to reproduce. The shields she used to protect Minato's mind were one such construct she used often.

She also used it to give herself a body.

At first, she hadn't thought to use it for such a thing, seeing as there was no real point to it. However, a conversation with Minato when he dove into his mind one afternoon (and she would really have to figure out how he did that sometime) jump-started the whole thing.

"Y'know, it's kinda weird," he said, kicking his legs where he sat on the little couch she had made just because she could.

"What is?" she asked.

"You, kinda. I can see you and I know you're there, but sometimes it's just… weird," he explained in that way that said nothing at all. Until he added, "You look like a shadow."

She flinched. "A—A what?"

"A shadow," Minato repeated, looking at her strangely. "You know. All dark and kinda misty. Which is why it's weird because you're pretty warm. Shadows are cool, aren't they?"

Oh. He meant actual shadows and not the monstrous kind. That was a relief.

Still, Tamamo grimaced. Actually learning what she looked like from his point of view made her uneasy. What would happen later when he went up against actual Shadows and compared their dark bodies to her?

So, using her self-taught lessons on mental construction to guide her, she focused on trying to give herself a body after he left, returning to reality. It was significantly more difficult to do as she was using it on herself, as well as the fact that creating the image of a human body was much more complex than forming a flexible mental shield or a piece of furniture. She could only be grateful that she only needed the outer image to be created and not the entire structure, organs and all.

When she could get the general shape in mind, it just became a matter of filling in the rest of the image.

Now, when it came to her past life's appearance, Tamamo admitted that there was nothing for her to be ashamed about. She had been average in looks, maybe even pretty depending on the angle, but she had certainly been comfortable in her body. It would be a great comfort to be able to settle back in her own skin, so to speak, while coping in this alternate universe.

She also admitted that it would be very boring. She could just hear her mother chiding her on being unoriginal. Infinite possibilities of how to look and she chose herself? What a shame! What a waste!

Her mother's nagging was always a motivating factor (even when not actually there), and so Tamamo formed something else. Still not quite original, but better than her first thought.

The female protagonist of Persona 3 Portable.

It made her laugh when she completed it, looking over herself in her new appearance. There it was, the two protagonists in one body. A fanfic waiting to happen if it hadn't already.

She didn't go with the Gekkoukan uniform to avoid suspicion, instead creating some clothes that looked nice since she couldn't exactly recall any of the actual outfits. But even without the iconic uniform, her new appearance was still how she remembered the female protagonist looked like. Or, at least, pretty close.

She might've gotten a few things wrong, like the shape of the eyes or the precise shade of hair and eye color. The hair, at least, was probably redder (pinker, really, but she wasn't about to admit that; red sounded much cooler) than canon. But she was satisfied with it and, considering how the female protagonist was practically Minato's opposite anyway, the color fit.

The next time Minato dove into his mind, she grinned over his childish enthusiasm at seeing her change shape.

She could've gone without the comment of her really acting like her namesake, though.

Years passed.

Minato, for all his words otherwise, became more and more jaded as time marched on. His reclusive habits got worse, exacerbated by his introverted nature.

The words of his peers didn't help. Neither did the constant moving. They watched him whenever he came to class, proclaiming him gloomy when he preferred to stay alone than spend time with anyone. But what was the point if he wasn't going to be there long anyway? That was always his argument when Tamamo asked him about it and, for the life of her, she couldn't find it in herself to argue.

Besides, on the rare occasions that he did hang out—usually with cousins or some other family member and almost always at Tamamo's urging—they called him weird for his habit of staying so quiet that they sometimes forgot he was even there.

Minato was a strong kid with pretty tough skin, but Tamamo knew how easily and quickly he could be worn down. She did her best to mitigate the damage, protecting him from his own thoughts, but some emotions were too strong and tore through any defenses she could put up.

In the end, all she could do was cheer him on from her little corner of his mind and watch with a heavy heart as he locked away his childish self in order to grow up and survive.

Gone were the books of mythology and wonder, replaced by an mp3 player with the volume turned up loud enough to drown out the world.

Gone were the days when he was honest and true to himself without thought, replaced by a defensive mask he wore for each person that interacted with him. Respectful and almost open for teachers. Distant politeness for family members. Detached interest for his more annoying peers. And so on.

Tamamo watched and feared, no matter how he tried to reassure her that he was okay and that he would never be able to do that with her.

"I can't exactly fool someone that lives in my head," he reasoned with an almost cheeky grin.

But it wasn't that that she was afraid of. Just about everyone had different masks, different facades, that they showed other people. And anyway he did have a mask for her even if he said otherwise. He just interacted with her so much that he didn't realize it even existed.

No, what she worried about was how reliant he was on each mask. Even she had a hard time keeping track of who he actually was underneath it all sometimes, and she lived in his head. Was this what would make him so adept at forming Social Links later on? But if all he showed was another face, another mask, readjusting himself for every person he met, and not his real self… was it really a true bond?

She didn't know. But maybe, she hoped, maybe the promise of having someplace to settle down at for more than a few months would help. He couldn't interact with people for too long because pretending tired him out. As much as she feared it, the fated year could be good for him.

In the meantime, she provided support as usual, giving him a place to retreat within himself when reality proved too much to bear. She gave him distractions in the form of mental lessons. Despite his protests, she taught him how to shield his thoughts from her if he wished, teasing him about how there were some things an adolescent male thought about that she didn't need to know. His embarrassment and meek acceptance afterwards was relieving (and hilarious) in its authenticity.

She learned more of who he was day by day, wishing she could record the little moments of his life. Like his first time visiting an aquarium, or his reaction the first time a girl called him cute (which would pile up so much that he eventually became desensitized). Memories she could have shown him to indicate how far he'd come later in life… if… if he got far enough at all.

("I should tell him," she would say to herself when the grief and terror of what was to come became too much to bear. "I should tell him. Prepare him for the tasks ahead. Somehow.")

(But then he would talk to her, the remnants of his innocence shining through his impassive demeanor, and she would fall silent.)

As his sixteenth birthday came and went, Tamamo watched with no little trepidation as Minato prepared to move yet again—only this time, to Iwatodai. To Tatsumi Port Island. The Gekkoukan High School uniform was sent to him in the mail, which he hung up to wear when he finally set out.

When she went to look, she observed that the chains around Death's door had loosened, allowing it to creak open just the tiniest bit.

She sighed. "'And so it begins'… right?"