The next morning Aeria and I reconvened at Elsa’s Greenhouse.

Unlike the academy greenhouses that were aboveground, this one tended to by Elsa was partially underground. She raised and parted a large slope of earth behind their home and solidified the soil so that they would serve as walls while the panels above allowed heat from the sun to pass through. It housed plants that she grew that weren’t suitable for growth within her home.

Inside, the Mountain Spirit gestured and caused the vines lining the glass to shudder as the thick leaves that were growing from them spread to form a curtain. It filtered out the view from above as what looked to be bioluminescent growths on the unexposed side shed gentle light. That was new.

Her appendages then elongated, the fibrous digits gingerly placing the Solana in a particularly colorful patch of flora and soft soil cordoned off by woven vines to form a play area. It immediately began to toy with the flora that was surprisingly robust, so I could only presume she had tampered with them to be durable enough for such activity.

“So, what do you think?” Elsa inquired, turning back to us. “I wanted to make this place suitable for the baby, so Wilhelm and I played around with incorporating the bioluminescence components that can be found in some flora into seedlings. The leaves absorb sunlight through the panes and can then shed the excess like this.”

“It’s pretty,” Aeria said.

“It is quite impressive,” I admitted, adjusting my glasses. “But should I presume that we were brought here in service of privacy as well?”

She nodded and then glided over towards the back of the greenhouse using the flattened soil acting as a makeshift walkway. With a gesture the earth parted and from an unknown depth emerged a sealed storage chest that was roughly half my size. She opened the lid of it and pulled a case of some kind out before she turned to face us. “I need to see for myself what you two look like while joined with one another. That’s what we’ll work on first.”

The small case was made of near-translucent crystalline glass. There were numerous chunks of crystals of various sizes partitioned into slots within it. I sucked in a sharp breath once I realized they weren’t merely stones that were attuned to elements or had aspects of it like Igniem or Glaciem. They were each elementally-attuned mana that was condensed and compressed to the extent of crystallization.

I could only presume that the case was shielded in order to prevent any of it from leaking out. Even one of those crystals would be more than enough to have an adverse, if localized, effect akin to what happened to the flora and fauna exposed to the mana that Alice found from the eviscerated spirit. Not to mention the unpleasantness of death by mana poisoning.

She entwined the case with the digits of one of her hands while the other reached into the storage chest and pulled out a smaller casket. Two of her fingers managed to get it open and she retrieved a bangle of some kind before shutting the storage chest. Then she approached us. “Put this on.”

I took the bangle and looked it over while Aeria floated just over it, dark eyes gleaming with curiosity. There were symbols similar to the gateway stone when active on it, as well as a precious gemstone of some kind in the center. And while not being too versed in metallurgy, I could tell from the texture that whatever composed it felt somewhat different from normal metal.

Then I placed it onto my right wrist and felt the change spreading through my body. It was strange. The best way I could interpret it was that it felt like there was a membrane layering my body, wrapping it in a skin-tight veil. “That… was mildly unpleasant.”

“It takes some getting used to,” Elsa assured me. “That bangle is designed to act as something akin to a double-layered filter, screening out all external sources of mana. You should be safe now when I open the case, but let me know if you feel sick immediately.”

I felt a little tense as she opened the case. But there was no overt feeling of sickness or other symptoms akin to mana poisoning. It seemed the bangle was operational. “There’s nothing amiss.”

“Good. Then we can proceed.” She extracted a single, pale-green crystal from the grouping within the case and then held it out. “Aeria, take this. We’ll use it as the catalyst for the transformation.”

Aeria gripped it with both of her arms while pressing it against her body as she flew back towards me in a hurry, only for her attempt to merge left her bumping against my chest. She drifted backwards midair with a small frown forming on her thin lips. “I can’t go inside him.”

“You’ll have to use the gem on the bangle,” Elsa explained. “It should let you in since you two are bonded, meaning it’ll register you as a part of him and the crystal will provide the bridge for the change.”

I held out my arm so that she could land on it. Aeria pressed the crystal down on the surface and her dark eyes folded in. The gemstone took on a verdant hue and the ancient writing began to shine. Then they both vanished and the change happened.

Unlike the last time, when it felt like my body was torn apart, it was more like a gentle breeze began caressing me. The wind whistled as it washed over me, taking away some of the sense of mass and solidity that made up my body. I was left feeling like I was floating on the air even with my feet on the ground.

“So it did…” I glanced at my surroundings to see the various colors of the air around me. It was as vivid as I remembered. But the lack of strings led me to suspect that Aeria had already reduced her presence within me. “It feels more comfortable than the last time.”

“Well, you both performed a rather unstable joining using the mana surrounding you for your initial transformation,” Elsa noted. “For mono-elementals such as Aeria, it’s usually less volatile if you use the predominant element of the spirit in question as a catalyst and that bangle works to slow the gradual dissipation—especially on this side.”

And there was nothing purer and replete with the Wind-aligned mana than the crystal she offered to transform us. The conversion rate was one-to-one with nothing wasted. Between that and the bangle that she’d given me, I had to assume that this was what would essentially be what our merged form would be in a stabilized condition.

“Probably not in your current form. Your present state is balanced on the scale between the two of you. You’d need to assert yourselves into more of a spirit before that could work.”

The moment she said that my sense of gravity and solidarity left me. It felt like I was falling but something was pushing me up, while the world itself was fading away into mist. The dizzying hues that swayed, swirled, and meshed together were starting to make me feel a pulling sensation—

“Stop it this instant,” Elsa said firmly. “If you push too far so quickly, you’ll break the symbiosis.”

And just as quickly as it came, it vanished. I gained mass and form when my weight returned nearly in full from before we melded. At the same time whatever was holding me aloft in the air vanished rather abruptly, so gravity reasserted itself.

Rather uncomfortably, I might add.

“It’s alright.” Elsa extended her fibrous digits to help me up as I avoided rubbing where the impact happened. It would be rude to do so in the presence of a lady. “You didn’t know. But before you do anything else, please let me explain how it works.”

“Yes,” I said, looking at myself to see that I almost looked…normal. Aeria went a little too far in the other direction it seemed. “That would be best.”

Elsa nodded and then gave us a general summary of our situation. Apparently, our union operated on something of a sliding scale. The more one of us asserted ourselves, the more of that aspect we’d take on.

“Right now, Aeria has suppressed the majority of her presence inside of you. That means you’re essentially just human with a few traits that might show up. It also means that if something happens to you, it’ll affect you almost as badly as if you weren’t together at all. That being said, there are some benefits to this state.”

I listened attentively as she explained that the current state didn’t burn away the mana used to bridge the two of us together at such a high rate of consumption. The bangle prevented the excess from leaking out as much as it stopped the external mana from entering my body and killing me. But keeping the membrane intact while maintaining the spirit symbiosis required was costly, so remaining closer to human meant that its cost was negligible unless the membrane was damaged.

Second, since spirits usually recognized one another by feeling the quintessence of another spirit, Aeria was effectively invisible to them. Not every spirit had the same concept of sensory recognition to humans that Aeria and Elsa did. So that meant if we needed to mask her presence we could do so.

Lastly, merely having her within me would grant some passive traits. Alice’s blanket immunity to heat and gaining magic were probably excessive mutations due to her own contract being forced upon and not formalized, so I shouldn’t expect anything so grand. Instead, it would most likely be something akin to feeling the shift in the air instinctively.

“It’s probably safe to presume Alice’s current state is something akin to this one then?”

The Mountain Spirit confirmed my hypothesis. “An unstable variation. The fact that you’ve spent years together and Aeria only noticed the spirit when that happened meant it was actively suppressing itself to a near-absolute state. It must be quite stressful to avoid doing any lasting harm to her since they don’t have as much leeway as you two.”

“It wouldn’t help. That bangle only works on those with a proper contract. It would do more harm than good because we don’t know how interwoven they are.”

“I was still a valid suggestion,” I noted upon feeling Aeria becoming deflated. “Even if it won’t help her directly, it provides another avenue for us to consider potential alternatives.”

“More options are always better when dealing with a problem,” Elsa agreed. “Continuing on, Aeria try slowly making yourself bigger again. Not too fast. Just until it feels like you were before you tried last time.”

The change happened again. I was prepared for it this time, so it wasn’t a surprise when I felt just a bit lighter and the colors in the air became more vivid.

He petrified cast of Elsa’s head bobbed. “There. Now you’re both in close equilibrium with one another. Neither a full spirit or a full human, but something in-between. Realistically, you’ll probably stay in this form while you’re on the other side—both for the sake of hiding the fact that you’re human and for safety.”

“Is it really that simple to fool a spirit in this state?”

“Wild spirits don’t really pay much attention to physical appearance and attributes, given how we essentially just force our quintessence and mana into a suitable vessel or take on an archetypical shape. Unless they have experience with others like you two, or does a deeper probe than they should, it’ll be fine.”

“If you say that it’ll suffice then I will take your word for it,” I stated, before turning to the other issue. “But could you clarify what you meant when you mentioned for safety’s sake?”

“Monsters thrive in mana-rich environments with no humans to cull them. The worse they can do to a normal spirit is simply scatter their corporeal form. It’s a different story for you, Sweetie.”

Ah, that made sense then. It’d take time for a spirit to reform but, as long as their quintessence remained intact, they could do so eventually. The only exception that I knew of was these fiends that the higher spirit feared, but our current state was apparently a bane towards them.

On the other hand, I was much more vulnerable as a human. If the shell provided by the bangle broke, then it was safe to presume our merger would become far more unstable until it mended itself. If symbiosis dropped without the bangle’s shell, then we’d be back to the previous situation that we’re trying to prevent. And even if it didn’t, the monsters could tear apart my frail body quite easily if they were that vicious and strong.

Elsa continued. “This form isn’t as vulnerable as the other one, but you’ll still feel whatever tries to hurt you. Plus, you only have limited access to the Aeria’s dominion and inherent abilities without her asserting herself.”

“There are two problems with that, aside from the increased mana cost of fully manifesting,” Elsa noted. “The first is that we don’t know just how far you two can push that threshold without the safeguards inherent to the contract kicking in and forcing you to separate. More long-lived spirits tend to have a more rigid threshold, but you’re young enough that there should be more flexibility.”

“And the second?”

She hesitated for a moment. “…It’s not common knowledge on this side, but spirits can essentially subsume another of the same kind or with overlapping dominions—quintessence and all. If the two spirits of the same kind are roughly around the same in terms of their quintessence, then they’ll just become a new entity with both sets of experiences and abilities. But if the difference is significant then the lesser of the two is basically dissolved into the greater being.”

“…You’re saying another Wind Spirit could actually cannibalize her?”

“Sweetie, that’s not quite the right word for it. It’s…” She trailed off in thought for what felt like forever before sighing. “I mentioned before how I didn’t really gain awareness of myself until I met Theo’s ancestors, right?”

I nodded.

“On the other side, most treat themselves as part of a collective because individuality is something that needs time or exposure to manifest. There’s nothing really wrong with becoming one with another for good since they’re just consolidating themselves. It’s like how water vapor meshes together until it condenses into a raindrop. It’s just something that happens in nature.”

Elsa set her hands on my shoulder—or rather our shoulders. “And that’s fine. Individuality isn’t treated entirely as uncommon. Some of the mature spirits even encourage it by taking a small portion of themselves and then implanting it into newly formed spirits. That way it serves as a foundation that can be built off of so they can develop their own individuality as well.”

“As fascinating as that is—” And it was a fairly interesting topic that I would love to ruminate on at a later date. “—I would prefer that her individuality not be at risk. How dangerous is it for her to be active on the other side?”

“She’ll be more vulnerable to such a thing the further she asserts herself,” Elsa admitted. “But to try and subsume her completely they would also have to try and incorporate you as well, Sweetie. Human quintessence happens to be a lot more difficult to do that with and you’d most likely be able to fight it off by just forcing yourself to the forefront. But whatever they take from her will make her much less than she was.”

Spirits grew with age as their experiences and longevity added to their quintessence. To lose any of it was to lose something that made her who she was. Her personality, her memories, her habits—all of them could be at risk.

And I could only presume that if the spirit in question was actually capable of subsuming myself as well, it would be identical to the crisis with Alice. Everything would be wiped away. Everything we were would be gone.

A haunting silence permeated the greenhouse after that until the sound of the Solana’s cries for attention rang out. Elsa removed her hands and then went over to her child, taking it into her arms and gently rocking it in a facsimile of a mother. Then she looked back to us and spoke softly.

“That was part of why I was so forceful when I stopped the two of you. Especially when I figured out that you were effectively going in completely blind. I don’t know where the gateway you entered before took you and I can’t really guess since they aren’t perfectly parallel between the two worlds. But I do know where the one here will take you and what’s on the other side.”

“A very aggressive Wind Spirit,” she explained. “It’s not one that can be reasoned with and any spirit that tries to exercise dominion over the air it claims as its own attracts its attention. We need to avoid it at all costs, but I believe that we can find a lead on where you need to go next at some ruins that aren’t too far from there.”

“If that’s the case then it’d be very helpful,” I conceded. “But there’s the matter of time. I cannot disappear for large stretches of it while still being expected to return to the manor. At least not until the wedding is over.”

“Then we’ll go on the day of your departure.”