When I first heard about Gundam Build Fighters and how it involves people fighting one another using Gunpla figures, I thought it would follow the concept of those totally-cliché plotted animes that were aimed for children such as B-Daman and Beyblade. But after watching the first season, I finally realized how wrong I was. Gundam Build Fighter was a total killer.

Watching the last episode of Gundam Build Fighters Try a few weeks ago had led me to make this fanfic. While it was indeed satisfying to have team Try Fighters win the Under-19 category Championship not to mention the Meijin Cup, I kind of had this small feeling that there was something important missing in that particular episode so I decided to add a few more things into it.

Hope you guys enjoy it

A Promise to be Kept

It was fine day here in Tokyo, Japan. The Under-19 category of the Gunpla Battle Championship had just ended more than a week ago whereas the Meijin Cup concluded just recently. While everyone was happily enjoying their relaxing break from both of the major events, Kijima Shia of team Celestial Sphere was having none of that.

Why? Because it was time for her and her big brother to return back to their home country.

"Ready to go, Shia?"

The lavender-head paused her packing to glance at her brother, Kijima Wilfrid, who was standing by the door entrance with his arms crossed. While majority of the public sees him as an intimidating antisocial person, Shia knew that he was anything but that.

"Almost, just need to gather up my Gunpla kit next and I'll be done." She replied as she clasped the luggage shut.

"Alright but make it quick. Uncle said our flight is coming this afternoon."

"That's Coach for you." Their uncle's voice rang from the living room.

Shia nodded, completely disregarding their uncle's words regardless how many times he reminded them about it. "Understood."

With that said, Wilfrid left the scene to do packing of his own. Shia waited until he was gone before heading to her worktable where various Gunpla pieces and tools were laid.

As she neatly inserted all the things into a second luggage bag, the only female member of Celestial Sphere spared a glance to her signature Gunpla who was prepped on a stand, the GNW-100P G-Portent, gleaming in all its glory courtesy of the sunlight from the opened windows. The same Gunpla she used for the championship. By far, it was her most proud work piece but Shia intends on improving it more in the near future, especially if she wants to be in even ground with other participants of the open world tournament.

Once she was sure it was in tiptop shape, her sparkling irises then averted its attention towards the object that was lying beside her custom made Gunpla.

Few days after the championship with team Try Fighters being the victor, a party was made at the Kousaka's café slash restaurant to celebrate the happy occasion. There, several people such as the Meijin and team Try Fighter's close friends were invited; this includes the members of Celestial Sphere as well. Naturally, they were skeptical about this considering how the party also reminds them of their loss but they accept it regardless so as not to disrespect them.

Plus, Shia got to spend more time with Sekai at the party so she wasn't complaining.

During the party, Shia's mischievous demeanor came up and she decided to tease Fumina and the other twin tailed girl (Gyanko, was it?) by taking a surprise selfie picture with Sekai. Naturally, their response was anything but happy and that was what Shia was aiming for. Moreover, she got herself a photo of her with him so she didn't regret her actions or whatsoever.

The picture wasn't exactly picturesque not to mention was aligned in an improper angle but such small matters didn't matter to Shia, what did matter was the redhead and the good memories lying behind it.

Shia sighed as she gently ran her fingers along the glossy surface of the photo. Things won't be the same once they're back at their home country, especially without Sekai and team Try Fighters around. While it's true she had a few more friends back inside and outside the Gunpla Academy, they were nothing more but mere accomplices to her.

In the end, the lavender-head dropped the subject and went back to packing up her tools and necessities; there was no point in divulging herself into such negative thoughts, after all. If you lost something valuable, just let it go.

Little did she realized that a person was actually standing right in front of her doorstep, apparently having seen what was happening within the room.

…

Few hours later, the siblings and their uncle arrived at the Tokyo International Airport where Adou was apparently waiting for them.

"How's your arm now, Adou?" Kijima asked. Despite his monotone voice and cold demeanor, the captain of team Celestial Sphere was actually quite concerned about his teammates' welfare.

"It felt like it could snap off any moment now." He answered back before shrugging his shoulders. "But it's nothing I couldn't handle."

"That's good to know."

As the conversation continued on without her participation, Shia couldn't help but repetitively glance at the entrance. Her breath hitched when she saw a familiar mop of red hair among the crowd going into the departure zone, only to be disappointed when she realized it was an entirely different person. And to make things worse, the person had his arms linked with a girl who obviously was his lover. Envy filled her as she noticed how happy they were with the company of one another.

"Something the matter, Shia?"

The lavender-head broke out of her stupor and turned to him; apparently her team members and uncle had stopped talking some while ago and was now looking at her, no doubt puzzled by her out-of-place behavior.

"O-Oh, it's nothing…" She hastily replied back. "I just thought I saw someone familiar."

"I see. In any case our flight's here, let's go in before the immigration checkpoint gets too crowded."

"Right."

On the day she was planning on telling Sekai about her leave, the redhead beat her to it when he told her that his team had to attend several press conferences on that particular day. And if the reporters were as persistent as usual, it might take them an entire day before they were able to free themselves. In the end, Shia decided not to tell so as not to be a nuisance.

Of course he wouldn't come. Shia mentally chided to herself with a pained smile as she slowly walk along her big brother. He probably wouldn't even come if he knew about it.

At least that's what she thought, until a familiar voice rang throughout the airport hall.

"Shia!"

The said person evidently screeched to a halt at the mention of her name. It can't be. There's just no way he'd be here.

"Shia!" The person exclaimed once more.

Standing just several feet away from her spot, panting and sweating like he had just finished a marathon, was the very person she had been in turmoil with a while ago.

"Sekai…"

But how was that possible? The only people who were supposed to know about their departure were the members and mentor of team Celestial Sphere. How did he know they were leaving?

As puzzled as she had been, Shia didn't have the time to figure it out when the redhead ran until he was right in front of her, beads of perspiration still rolled down his face and soaked the white Kenpo school uniform he was fond of wearing.

"Sekai, what are you doing here?"

Despite the fatigue he was experiencing, the redhead sported a grin. "Can't I say goodbye to a friend?" He said jokingly before going serious. "Why didn't you tell me you were leaving today?"

Shia flinched upon hearing the pain behind his voice. As much as she wanted to do so, the lavender-head was never good with goodbyes, especially if it's with someone she truly cares about. It was just too troublesome. If anything, she would avoid doing such thing as much as possible.

"It's no big deal; you were busy with the press conference after all."

"No big deal? Of course it's a big deal!" He declared, surprising her (along with a few other occupants within the departure hall) greatly.

Realizing his mistake, the redhead spared a moment to calm himself down. "Will you come back to Japan?" He asked after regaining his composure.

Shia stared at him in the eyes for that. She could almost see the sad emotions flowing in the alluring vermillion irises of his, silently pleading for her not to leave. If she had the choice, she probably would've stayed but sadly, she couldn't.

"Of course I will." She replied back with a smile. "Me and big brother will be participating in the Open World Tournament soon so there's no reason for us not to come here again."

"You promise?"

"Cross my heart," She confirmed with a firm nod. Sekai slowly smiled at that and she couldn't help but smile in return.

"Shia, it's time to go." Kijima Wilfrid's voice rang throughout the hall.

Shia ceased eye contact with him to glance at her brother and the rest who now was standing near the immigration entrance, several feet away from their current whereabout. When did they got there, she had no clue. At least they provided them both with some privacy and she was really grateful for that.

Turning back to the redhead, the lavender-head spoke, "It's time for me to go."

The slight mention of that brought back up the sour mood once more but fortunately, it wasn't as saddening as before.

"Yeah…goodbye Shia."

"Goodbye Sekai." With that settled, the lavender-head turned around to leave, only to face him once more when an idea popped into her mind. "Oh, there's one more thing I'd like to do before I go."

"Eh, what would that be—"The Ace of team Try Fighters didn't get to finish his sentence when Shia did something the he truly did not expect.

Leaning close to him in a tiptoeing manner with her eyes gently closed, the lone female of team Celestial Sphere gave him a shy peck in the cheek. It wasn't actually planned firsthand but Shia figured she should at least give him one last hint before she leave, especially with how much of a knucklehead he was.

Confused and shocked like no other, Sekai could only give Shia a wide-eyed blank look that made her giggle shyly in response. Before he could utter a single word or even do anything, she ran towards the immigration checkpoint, quickly had her passport examined by the officers there, before heading for the dual automatic sliding doors. The last thing she saw before the two doors closed shut was Sekai's still-shocked expression, obviously still dumbfounded by whatever had just happened.

So what do you guys think? Was it good? Was it bad? Was it too fast? I was actually using a different method than the one I usually used when I wrote this one-shot so there might be a few small details that I've missed. If you guys do found it, do tell me so and I'd be happy to fix it.

Don't forget to review :D