Seika bolted through the streets of Synoria Outlook with Kaito in tow, occasionally abruptly stopping and glancing around before turning down another road.

With all the quick turns, Kaito wasn't able to tell whether Seika actually knew where she was going or if she was simply trying to comb every inch of town to find their cart. 

Glancing at Seika, he hesitantly asked, "Do you actually know where this place is supposed to be?"

"Yeah, right here"

She jarringly halted her entire momentum, causing Kaito to fall against her as he was still adjusting his balance. 

"...this place..?"

In front of them was a fairly large lot without any buildings except for a small shack off to the back corner of the lot. Neat rows of nearly identical covered wagons occupied the rest of the lot, separated by dirt paths that could be used to retrieve or return the carts.

"Yup, Synoria's famous cart rental with locations in almost every town!", she exclaimed, before adding, "known for great customer service", under her breath.

***

[Back at the inn, a few minutes prior]

Seika reached into her pocket to draw out the required fee, only to find it empty. In a panic, she patted herself down, only to find that what she was looking for was nowhere on her person.

"I took it off and put it away on the way here just in case I couldn't confirm Kaito's trustworthiness... did it fall off on the cart when we were unloading?"

In truth, what Seika was searching for wasn't some wallet or coin pouch, but rather a pendant that she usually kept around her neck, or at least somewhere in her posession, at all times. The pendant's main feature was a silver metallic piece with the left side being a sharp edge while the right appeared rather chipped and frayed. 

Despite seeming like simply a unique fashion choice, the pendant was actually made up of one of the shards of the Key of Creation, which Seika had obtained ten years ago, and her constant exposure to which gradually yet greatly increased both her mastery over mana and her physical capabilities. 

Being able to tap into the shard's internal space, Seika stored her gold within it, which could be easily retrieved whenever with a slight manipulation of her own mana. With all of these factors combined, she understood three major negative outcomes: that she'd be without the ability to pay until she recovered the pendant, that she'd lose a major source of her power and growth, and the possibility the shard could fall into the hands of some unsavory figure.

In the spur of the moment, Seika managed to temporarily resolve the issue with the innkeeper and hastily dragged Kaito along to search for her accessory. Yet, without the shard's massive mana pool, she was forced to draw upon her own mana, which quickly began showing signs of side effects after not having to entirely rely on her own mana for nearly a decade. 

Essentially, due to her lack of mastery over her personal mana control, she was unknowingly drawing upon her own aether, in a far slower and much more ineffective manner than Kaito learned to with Hayato's aether. And, with aether being the crux of a living being's existence, what she was actually doing was equivalent to burning her vitality in the moment to draw upon her connection to the shard.

Due to her familiarity with the key, she was able to faintly detect lingering traces of its presence along a certain route through Synoria Outlook, which eventually led the two of them to the town's branch of Synoria's cart rental. By this point, Seika could feel a splintering headache growing, yet she forced herself to push through it. For starters, she didn't want to explain the situation of the Keys and her relationship to one of their shards, which would've consumed precious time and risked involving Kaito in something far too large beyond the scale of World Zero. Furthermore, at the moment, she felt the need to uphold her role as a mentor, which to her meant she couldn't show weakness and needed to display her knowledge from which Kaito could learn.

The two of them entered the shack on the cart rental lot.

***

"What do you mean someone's already taken that cart?! It's been like three minutes max!"

"Hahah... sorry, you two, but a customer approached in a hurry just as I was bringing that cart in, and surely you must know how we cater to our customers", the old man running the shack jovially replied.

"Curse this business and their great customer service", Seika thought to herself.

"Which way did they go then? I've dropped something important on that cart and I need to get it back no matter what"

"She really must've had a lot of gold on her-", Kaito concluded, still not fully understanding the value of currency (as Hanakawa had functioned on bartering with their small community) and completely misinterpreting the item that Seika had actually lost.

"Hmmm... well, it's quite hard for me to help you out considering you're unwilling to divulge what you actually lost... but if I recall correctly, they were heading towards the North exit"

"North... alright, thanks for your help!", Seika blurted as she wheeled around towards the door.

During the conversation, Seika had stopped her tracking of the shard's trace to preserve her endurance, but by now, the traces had become too faint and intermingled with the mana signatures of others to fully discern. In a last ditch attempt to confirm the old man's directions, Seika forced a small amount of mana usage, causing Seika to stumble from a sudden intense burst of pain in her head as they reached the edge of the lot.

"Dammit... I've pushed myself too much... I really can't handle using my mana like this"

Before she could realize, Kaito had propped his body underneath her's and supported her as he set her down on a nearby bench. The two made for quite an awkward sight, with Seika being about a head taller than Kaito and his own build being much less refined than her's.

"You've done a lot for me already- and it's obvious how important this is to you, so no questions asked, I'll take it from here"

For the first time since fighting Seraphim, Kaito's azure aura surged forth around him, noticeably larger than before he gained his new body.

Similarly, this was the first time Seika had actually witnessed Kaito displaying his aura, the colors of which evoked a slight sense of nostalgia and homesickness in her.

As Kaito approached the Northern gate, Seika's awareness began to come to and she remembered a key detail she had never mentioned. Straining her body forward as far as she could without falling off the bench, she cupped her hands over her mouth and shouted, "What I dropped in the cart, it's a pendant! Look for that!"

Kaito initially reacted with surprise.

"A pendant? I thought it for sure was money or something of the like- Well, whatever, it's still important to her, and as of now, I can move the fastest between the two of us"

Kaito looked back towards her and gave a nod of understanding before continuing with haste.

"This kid... yeah, I'll tell him the truth once he gets back. He deserves at least that much after doing all this for my sake..."