1

"Hikari! Sana!"

His heart pounding, Kazuki shouted the moment the door opened. When he was greeted by a completely dark room, he frantically looked for the switch.

The lack of response from the call had worried him, but to see those fears of his slowly come true was a completely unpleasant feeling. After leaving the Amagi residence, he had lost contact with the two girls, and with Hikari, it was something that had never happened before.

Before he can press the unit's switch and proceed to regret his actions, the lights came on.

"Let's go and make some noise! Everyone's favorite idol, Yuki-tan is here!"

All the adrenaline within Kazuki fizzled.

Slowly getting the gist of what had happened, he was not thrilled. Yet, relief quickly replaced worry. Instead of the lively idol somehow having invaded his home, in front of him were the two girls dressed in idol apparel.

Sana and Hikari, wearing red and blue dresses respectively, stuck a pose meant to welcome him home. Both came with their own props, and they stood at the doorway dancing.

Hikari moved nimbly and gracefully, whereas Sana still acted with strong reservations.

It was only at this point when the appetizing smell of the hot pot and the cheerful singing of the two girls started sinking in.

"So, how was it?" asked Hikari.

"W-was it good?" followed Sana.

Kazuki did not know the proper way to respond. Instead, he bent his knees and sighed.

It was not long before the three of them had settled by the dinner table.

"Please, don't scare me like that again, Hikari."

"It's Sana's idea," replied Hikari before she took a mouthful of seafood soup. "She said we better surprise you with something, and I lent all my Yuki-tan merch. While you were out, we watched all her videos, too."

"Sana did?" wondered him. He was more surprised that Sana would think of such a thing given how hesitant she seemed at the doorway.

"Sorry, Big Bro..."

Kazuki put down his bowl.

"No, no, I'm not angry or anything. Right now, I'm just a bit surprised, that's all."

"I've spent the night showing Sana my Yuki-tan collection and videos. She's so into it she decided to throw a big surprise for you," interrupted Hikari. "She thought it might cheer you up."

"Thanks for the concern, Sana."

"Sana's real cool, though. Have you seen how her dance steps looked just like the real thing? I mean... she's a bit shy and all, but wait till she gets to show the real Yuki-tan those moves! So, when will Yuki-tan be coming back here? Will you bring Amagi here, too? You met with her this evening, right?"

Kazuki raised both hands.

"Whoa, whoa, whoa, it's not like I can just tell Kimura to come drop by. She's a busy person, you know?"

"I still can't believe it. Who knew that Big Bro, of all people, would get to be buddies with Yuki-tan herself? Especially after that Imperial Tracks moment."

"We agreed to never talk about that again..."

"It's fine. It's just Sana with us, Big Bro. Don't worry, I didn't tell her the whole thing," she mischievously put a finger on her lips in a shushing motion.

This only served to draw more attention from Sana, who leaned forward. Her eager eyes seemed to exude a hypnotizing gaze that he never expected from the yellow-haired girl.

Actually, everything concerning Sana was full of surprises. For so long, he always saw her as this shy, withdrawn girl. The one you'd like to cuddle and protect. The pure and innocent soul you'd hate to see upset.

That image had not changed, just modified, these past few days.

Turned out that looks can be deceiving, and he felt that the Sana these two days was a completely different person.

Is this what Sana's really like?

He thought so while bracing himself. It was not quite the same level as Hikari's boundless energy and motor mouth, but he felt that Sana can truly be a handful to have around.

She can also be assertive when needed.

Was this the effect of her now being a de facto family member? After all, she did show unexpected agency when confronted with her mother.

There was a lot more underneath the surface for this girl, and Kazuki himself cannot wait to find out.

"Big Bro..." Sana began. "What happened at Imperial Tracks?"

But first, he had to overcome this trial that will likely last throughout the night.

2

"Whew, that's a handful," said Kazuki before he crashed onto his bed. It's deep into the night now, but today has been a wild day, to say the least.

Throwing the cell phone to a side of the bed, he spread his limbs wide, enjoying the paradise that was his bed.

Not everyone could suddenly find himself having a foster sister on the fly. The Sana-Hikari combination tired him more than he would admit.

It's not that it's a bad thing. Certainly, having things become livelier in the household was great for Hikari. At least she did not have to just put up with this brother of his. She'll have someone to talk to now, and there's someone who can relate with her more.

Still, part of him felt the slightest tinge of guilt.

Was it really the right call to take in Sana? Granted, Ms. Sadohara knew about it, but what about Mrs. Kurashiki and Yura?

It just sucks that whenever he's left alone on bed, these things would always come bother him. He could play a mobile game, but what good will that do besides delay the inevitable? Besides, with the Magna Arbiter's power still on the loose, there's no time to be slacking around.

He rolled around his bed, trying to ease himself with little success. Such was the state he was when he heard three knocks on his door.

It's almost midnight already. It's rare for Hikari to be up at this time.

"Hikari, what's the matter?" he asked with a pretend sleepy voice when he opened the door.

"Big Bro... do you have time to talk?"

Instead of his little sister, it was Sana waiting for him. With her yellow hair looking disheveled and her pajamas hanging loose, he can tell that she was likewise troubled.

"Come right in."

He reached for the light switch when Sana held him by the arm. She shook her head, telling him that it was not necessary.

Soon, the two of them found themselves seated on the bed.

"Anything I can help you with, Sana?" Kazuki started. "Finding it hard to sleep?"

Sana meekly nodded, which prompted Kazuki to brush her hair with his fingers.

"Don't worry. I'm in the same boat," he chuckled.

"T-thank you for letting me stay, Big Bro."

It took a few seconds before Kazuki can muster a reply.

"No problem. I'm glad you're enjoying Hikari's company. She showed you all the Yuki-tan videos, huh? She's probably a bigger fan than the both of us combined."

Sana beamed at him. "Really? But you know her and became classmates with her. I think that makes you even better, Big Bro. Hikari's real jealous."

"I-I guess you can put it that way," replied Kazuki, remembering the conversations at the dinner table just hours ago.

"Yes, she did say she's so jealous you got to be so close with the pinnacle of idol culture."

"Pinnacle of idol culture, huh? That Hikari..." he sighed with a smile. "Well, if she's being too much for you to handle, feel free to tell me, okay?"

"That's what makes it fun. Here, I feel very comfortable. I love the place, and Hikari and you are very fun."

"Heh, I appreciate the kind words," dryly replied Kazuki. "But I don't think 'fun' is something I get called often."

To his surprise, he felt an arm go around his, and all of a sudden, Sana's soft hair was resting against said arm.

"If not, then maybe 'reliable' is better. I wish you and Hikari were my family instead. I like you, Big Bro."

Kazuki looked at Sana half-embracing his arm.

"Y-yeah, silly me," he said to himself before turning to Sana, gently brushing her hair. "Glad you're finding it great here, but it makes me wonder what your home really is like? A-ah, sorry. If you don't want to bring it up, it's perfectly fine and—"

"It's sad and lonely."

"Sad and lonely?"

"Mama just doesn't care. She gets home and all she does is complain about what I did at school or that I have fun with you. She wants to force me to a path, and she won't stop it. Even if I told her I wanted something else..."

"Ah, so she's that kind of mother."

Sana solemnly nodded.

"I feel that 'just doesn't care' is too hard of a word. Deep inside, she probably cares for you, even just a little bit."

"She sure doesn't show it."

"Speaking of, is that why you ran away? I know she told you that out of impulse, but for you to just do what she says and run off... I think I want you to tell me the full story."

"I just can't stand it anymore. She never treats me like her daughter, she never sees me as anything more than someone to brag about, and she threatened to cut me off from you and Hikari and everyone!"

"Now that's really a pain."

"Right? So let me stay with you forever. It has only been a few days, but Hikari and you are already a lot nicer than she ever was, and I am happier here. The two of you have been the family that I never had."

Kazuki took a while to process everything. Once Sana finished everything, it was his turn to speak.

"How about your caretaker? We only talked for a brief while, but she seems to be a nice person. Your dad?"

"Please, I want to stay here!"

Sana's grip on him tightened, and the youth got a better glimpse of her face.

"I don't..." Kazuki paused, catching himself when he saw the glint on Sana's eyes. Despite having a concerned expression, he smiled at the girl, gently patting her head once again.

"You know what? I'll allow it," he said after a meaningful pause.

"Really?"

He could not mistake the shock he saw on Sana's face. It was as if she herself did not expect him to say yes. That shock turned into a huge smile as she tackled him in a hug.

The two of them crashed down, landing on the soft mattress with a creak.

"But promise me this, Sana."

She looked at him with eager eyes while he started thinking of the right words.

"When you're ready, you have to return home. Eventually..."

"Eventually?"

"Eventually." Kazuki nodded. "Sana, you will eventually have to face your mother. I know nothing about your family nor your history, but we cannot keep running away forever."

Seeing the mood on Sana's face go worse made him hurry with his follow-up.

"Don't you worry, Sana. When that day comes, I will be going there with you."

"You will?"

"Of course. Who better to have your back than Big Bro here?" he chuckled. "It's a promise!"

"Thanks."

"Glad to have helped. Sana, I'll be leaving the door open for the night, so feel free to drop by in case you need something, okay? Don't worry about waking me up and all."

Getting off the bed, Sana nodded, her face bright and upbeat now compared to what it was moments ago. Seeing that was enough to put Kazuki at ease.

"Be careful going back, okay? Try not to wake Hikari up."

"Yes. Oh, and before leaving, I want to say something."

"Hmm?"

"The lights. Blue and calming but with a strong atmosphere. I feel comfortable seeing them around you."

"Lights?" asked a puzzled Kazuki. He then noticed the moonlight seeping through the window before opening the curtains full blast. "You like the night sky, huh?"

Sana did not elaborate further. She just gave a smile before leaving.

With Sana leaving the room, Kazuki found himself alone once again. Plopping down the bed, he shut his eyes, finally feeling sleepiness gripping him.

He still was not sure whether keeping Sana around was viable in the first place, but another day or two won't hurt, right? Besides, he did not want to break the vulnerable girl's heart, not after how she opened up to him and trusted him.

Before he can further lose himself in his thoughts, his eyes finally closed.

3

"Big Bro!"

Kazuki woke up with a start upon hearing Hikari's distressed voice.

Before he can process what happened, his little sister was at the side of his bed.

"What's going on, Hikari?"

"It's Sana! Sana's gone!"

"What?!"

His sleepiness evaporated in an instant, and he tried to get up. In spite of that, a heavy weight remained attached to his left arm, shocking him.

Out of the blanket came the source of the weight to an audible gasp heard all over the room.

Sana, still in a drowsy state, lazily stood up. She released her arms and legs from Kazuki's arm, and she yawned.

"Hi, Hikari," she sleepily said while wiping her eyes. "Good morning."

"Sana?"

Kazuki was in shock when he asked the girl who appeared by his side, but his surprise was nowhere near what he can see from his sister's trembling face. A mixture of horror and apprehension filled Hikari's face, and in wondering what the fuss was about, he looked back at Sana.

Then, it dawned on him.

He shouted.

At this point, the still sleepy girl had stood on top of the bed, but her long pajama top had been unbuttoned all the way to her abdomen.

"W-wait, what happened to—"

Kazuki's eyes traveled down Sana's body before he stumbled down the bed and onto the floor with a yelp, taking the blanket with him.

"Thank you for last night, Big Bro. I had the time of my life."

"Sana! Stop saying things that can cause misunderstandings!" stammered Kazuki in a panic as he looked away.

"Huh? But thanks to you, I was able to sleep well."

It was then that Sana looked down. Her facial expression never changed, and she remained unfazed, as if blissfully unaware of the situation.

A stark contrast to the other two people in the room.

"Huh? Anything wrong?" she asked innocently.

There was definitely something really, really wrong.

'Anything wrong?' is NOT the appropriate response for seeing your own pajamas dropped down, left in a crumpled heap around your ankles.

"Big Bro!" angrily yelled Hikari.

"I-it's not me! I swear she left before I went to sleep!" begged Kazuki.

"Eh? Eh?"

Sana blinked sheepishly, still oblivious when Hikari angrily began scolding her older brother.

---

Not long after, Kazuki and Sana found themselves sitting across each other by the dining table.

"So you're telling me that I was so deep in my sleep that you were able to get back in without me knowing?"

Sana nodded, causing Kazuki to stop in disbelief. Both at himself and at this girl for daring to do something like that.

"I feel a lot comfortable being with you, Big Bro. D-don't you like it?"

"It's not that, Sana. But there are things that.... Argh, how do I explain it?"

"Things that you're not supposed to do out of self-respect," finished Hikari, right when she put the pot of soup in the middle of the table.

"S-sorry."

"Don't sweat it, Sana. Big Bro's not gonna harm you or anything..." she squinted at her brother in a discomforting expression. "...I hope."

"I won't!" objected Kazuki.

"Yeah, I trust you," chuckled Hikari. "Okay, shall we eat? It's Sunday, so we have the whole afternoon to go somewhere again. Where would you like to go, Sana?"

"Hmmm..."

"Ah, I know! You haven't been to the aquarium, right?"

Sana looked on in silence.

"Aha! I knew it! I've heard Maria talk about it. I want to see all those things she was talking about! They say it's near a water park, and it's got a lot of pretty fish and even penguins!"

"Um..." Sana replied.

"Big Bro, wanna go with us later?" asked Hikari, now turning her attention to her brother. "Come on! Do it for Sana!"

"Hmmm... I don't have anything to do this afternoon, so let's go for it. But wouldn't getting tickets be hard? It's the newly-renovated one inside Eden, right?"

"Yes, it is! Oh, and Eden has a big mall inside, too. It's got lots of stores just like Samsara! Oh, oh, oh! There's also a movie theater that we haven't been to. I heard they got all the latest 4-D technology for the films and..."

"Okay, okay, take it easy, Hikari. I think it's best to pick one destination and make the most out of our afternoon there. We can take Sana back to Eden in the future."

It could be due to the last sentence that he caught a relieved smile on Sana's face.

"The aquarium it is, then!"

"Easy, Hikari. Why don't you ask Sana? She's our guest of honor, you know."

"So, what is it, Sana? Please pick the aquarium! Please pick the aquarium!" begged Hikari, clasping Sana's fingers around hers. It was an act that caused the yellow-haired girl to mutter an audible "eep" while Kazuki looked on in awkward silence.

"The aquarium," answered Sana.

"Not sure how much of that decision is yours, but alright," Kazuki answered before reaching for his phone.

Hikari and Sana, mostly the former, continued chattering while he hovered to Ms. Sadohara's number. He normally would have felt the excitement brewing in the air had he not been busy sending a message.

Besides that, he was also deep in his thoughts on how to budget his time. He wanted to help Sana to the most of his ability, but the hunt for the Magna Arbiter never left his mind. Tonight could be an important night of investigating Fragments just like before.

A few minutes after he sent the text over and let her know about his plans, the phone vibrated, prompting him to check his inbox.

Really?

He hurriedly typed a reply, refusing to believe what he had just read.

Sure enough, another reply came, and he turned to his sister.

"Hikari, Sana, I got some amazing news for you."

The two girls stopped almost instantly in attention. In response, Kazuki showed them the screen of his smartphone and watched as the girls' eyes grew wide.

On the screen were voucher numbers for tickets. Four of them, in fact.

"Let's get there around the opening hours, shall we? And before that, we get to invite someone to come with us," he suggested with a smile to the cheer of his little sister.