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The knowledge of Kaiba Seto’s actual birthdate was kept so tight lipped amongst the few people that he was intimately acquainted with, Mokuba was sure the only other people to know, outside him or maybe Isono (the man never said anything one way or the other), were the Japanese government. He knew that his brother liked it this way, enjoyed this speck of privacy and control. He had never really gathered a full response out of Kaiba about why that was anything more meaningful than ‘it’s just another day on the calendar’.
Mokuba thought birthdays were special. They marked the day that someone—something—was kind enough to visit life upon them. Maybe that was why Kaiba was, often, so careful and particular in regards to preparing for Mokuba’s birthday in comparison to his own. More questions left unasked, answers he didn’t need. As long as his nii-sama never forgot, he didn’t care if anyone else knew. But he did love it when his birthday came around, and was more than willing to share it with the world, to hoard the gifts from his growing fan club, but Kaiba was the only one that mattered.
Which was maybe why only Mokuba knowing his brother’s birthday mattered, too.
There were people who tried to guess, of course. That was the standard. So much so, Mokuba was positive he had read a heated article, complete with a clickbait title that was quickly forgotten, entirely on the subject. No success was found and, as far as he noticed, no ground was made. That field on the Wikipedia page was still empty.
That day was treated like any other day of the year. Sometimes there was work, sometimes there was play. But there was never anything extravagant done. No parties were thrown, surprise or otherwise. Mokuba respected his brother’s privacy enough to say nothing, not even to Yugi or Jounouchi, knowing that they would try and set something up.
But nothing could stop Mokuba from giving gifts. Discreet gifts, brotherly gifts. Handmade gifts. Nothing that could be misconstrued by anyone as something other than a little brother giving his big brother something sweet. There weren’t any cards or cakes or balloons, even though Mokuba had really wanted to fill the executive office with a colourful array of them, just to watch Kaiba open a window and the let them drop down onto busy Domino streets.
But on Saturday, October 25th, on the day that Kaiba was to turn 20, Mokuba had a gift in mind. He has handmade a dragon statue, one he was very proud of. Everything was just right, down to the last glossy coat. But he’d been in too much of a hurry as they prepared for a weekend long convention in New York City. He had only remembered it was still hidden under his bed when their flight took off late Thursday night.
Something else needed to be done the day of. Mokuba just didn’t know what.
All of Friday had been devoted to Mokuba sitting on panels with people thrice his age, answering questions Kaiba couldn’t be bothered to respond to while he worked out the details on their presentation which, Mokuba suspected, had been intentionally put on the 25th.
Late into the night, when the minutes slipped by and changed Friday to Saturday quietly and without notice, Mokuba trekked down the lower levels of the hotel, across the large but empty rooms where the convention was being held, a laptop tucked under one arm, a mug held in one hand.
He was still thinking. Plotting. Planning. But coming up empty.
Mokuba found the room Kaiba was in. He stood at a desk, staring at his own laptop, the chair kicked off to the side at some point. The rest of the square room had rows of computer along each wall, a temporary lab that KaibaCorp had set up for the weekend. A place for all the engineers to work.
“You gonna sleep?” Mokuba asked.
“Are you?” Kaiba rebutted.
“Nah. This city doesn’t know how to sleep. I’m pretty sure there’s a parade out there right now,” Mokuba said. He set the mug by his brother’s laptop, left there no more than two seconds before it was swept up in Kaiba’s hands. Mokuba chuckled. “What are we workin’ on?”
“Still smoothing out kinks in the neural interface.”
“How far have you gotten?” Silence from Kaiba. “That good, huh?”
“It’s just giving me a headache right now.”
“Well,” Mokuba claimed the chair his brother had pushed away and sat it by Kaiba, climbing up into it. “I don’t think your gonna finish that in twelve hours.”
The coffee mug was raised. “Perseverance hasn’t let me down before.”
Mokuba chuckled. “Yeah, okay. Good luck with that, nii-sama.”
A hand was settled on Mokuba’s shoulder, even as Kaiba’s eyes never left the screen in front of him, and shook the smaller shoulder. Mokuba leaned his cheek against the hand in a semi-hug.
Mokuba opened up his laptop, ditching the chair and pulling himself underneath the desk to plug it in with the mess of other wires, all interconnected with one another to share an intranet connection.
And right there, the gift idea spawned in Mokuba’s mind.
For several moments, hearing his brother occupied with rapid-fire typing, he carefully moved wires around. At one point, he unplugged Kaiba’s to a questioning “Mokuba?” A to which the boy squeaked “sorry” as he plugged it back in and popped out a moment later.
“It’s a rat’s nest under there. Couldn’t find an outlet.”
“Mmhm.”
The smile was pinched back, Mokuba refusing to allow his plan to be thwarted. He figured out a unique gift, only for his brother. At least for now, until he could get his hands on the physical present. “I’m gonna work on the code with you, that okay?”
“I’ll send you the updated files.”
Mokuba’s fingers hammered away at the keys, occasionally checking to be sure that he was still connected to each terminal in the room, that Kaiba hadn’t took notice and limited his access. If that went away, it would screw everything up. But Kaiba’s was too engrossed in the back and forth of his own project, a relief to the younger brother.
“Hey,” Mokuba said, after what felt like two hours of typing in silence. “I think something’s wrong with my computer. I was in the middle of something and it became stupid frozen. Can you look at it nii-sama?”
“Have you tried everything?” Kaiba asked, and he pushed away from the desk, side stepping over to Mokuba’s.
“Duh, or I wouldn’t ask you.” A few keys were pressed, but the screen never changed.
Mokuba stepped back and away, standing at Kaiba’s workspace. He observed his brother, with face a-glow and in zombie-like focus, before turning to Kaiba’s computer and poking at the keys, making sure to save any work before executing his master plan. “Mokuba whatever you did to this...you really did it.”
“Oh?”
“I can’t even begin to think what you were trying to do when—“Kaiba’s head swung over, catching Mokuba in the act, eyes widened. “What are you doing?”
“Oh...nothing...”
And all screens in the room went black, leaving only the gentle hum of the hardware. “Mokuba, you had better start explaining what....”
From Kaiba’s computer screen, characters began to bleed outwards, scrolling from one black screen to the next, reading:
Happy 20th Birthday, Seto Nii-sama. I love you very much. <3
Kaiba stood back, lips parted but silent as he observed the ticker of characters as they circulated around all of the monitors. His body turned to read all of them, the message flowing seamlessly.
Sticking his hand out, pointing to the space by his side, Kaiba beckoned Mokuba over without words. The boy hung his head and curled his hands at his chest as he approached, afraid of this result. “I’m sorry. I know you don’t like me hacking into things. I get it if you’re mad, nii-sama, I just really wanted to do something. I had left my real gift at home on accident, and I didn’t want to do anything in front of anyone but I still really wanted to dosomething and...”
The arm pushed Mokuba into Kaiba’s side, tight and warm, fingers running through the shaggy, raven hair, before he dropped onto one knee and enveloped Mokuba in a hug. “I love you, too, kiddo. You are something else.”
Mokuba threw his arms around Kaiba’s neck. “I learned from the best.”
“Just don’t go taking over and crashing any satellites,” Kaiba said. As if he needed to give his growing felon any ideas.
“Only because you asked nicely,” Mokuba laughed. He went back to his computer, turning off the message with reluctance, the other computers in the room dying down. But he left it scrolling across his screen. When Kaiba had returned to his own desk, he seemed to mechanically go back to work, as if Mokuba expected anything else.
But there was a smile, wide and proud, on Kaiba’s face. That was enough.