So, when I originally thought of this, I had intended it to be a one-shot. But it is looking like it will become a multi-chapter fun-filled affair. Which is fun, but on the downside, I highly doubt I will be able to finish the story in its entirety before Christmas, though I will certainly try. I'm a slow writer, so I apologize in advance for any delays that may prevent me from making my self-imposed Xmas deadline. :) I'm trying to make this story equal parts humor and fluff, but if you prefer to see one more than the other, feel free to say so, and I will try to do so! Also, on a side note, I've kind of written Mokuba a little bit younger and more innocent/naive than normal for the sake of the story.

Warnings: Seto/Joey pairing, with fluff. Lots of innuendo. Slight swearing. Seto might be a little OOC, but I figure after dating Joey for a while, he's bound to have loosened up a bit and had his icy heart melt a little. :)

Also, if you know in your heart that Santa is real, I don't recommend reading this story.

I Saw Brother Kissing Santa Claus

"My life is over!" Mokuba cried, dramatically bursting through the front door to the mansion, a swirl of snow flurries dancing in after him.

Mokuba, upon hearing no consolations of pity, looked around to see a decisive lack of persons standing nearby to gain sympathy from. That wouldn't do. He quickly stripped off his winter coats and snow boots and trudged through the vast rooms until he found himself in a deserted wing of the mansion, in a smaller living room where a couch sat with its back to him, and a cozy fire going on in the hearth. He repeated himself. "My life is completely over!" he shouted.

Two heads instantly popped up from behind the couch in surprise, looking wildly around. "M-Mokuba! You're…you're home early," Joey chuckled nervously in a voice that was an octave or two higher than normal. Mokuba noted that both Joey and his brother were red in the face and their hair was a tousled mess. They were probably, his young and innocent mind provided, just playing a game of wrestle, like he would do during recess if school had not already been let out for Winter Break.

Joey coughed hastily. "Uh…just how long have you been standing there?"

Seto eyed the doorway, as if fearfully wondering the same thing. "I thought you were going to be playing with Rebecca all afternoon?" he asked as smoothly as he could, while also hoping that he had not inadvertently scarred his younger brother for life with any activities he might have become witness to.

"I left early," he pouted sullenly. "But that doesn't matter! Because there's no point in living anymore!" he wailed a tad melodramatically, tears building up in his sorrowful grey eyes.

Seto smiled softly, and a little amusedly, and extracted himself from Joey's hold on his waist, ignoring the blonde's displeased whine. "I'm sure your life is not, in fact, over, Mokuba." Seto kneeled in front of his brother, who sniffled argumentatively in response, as if to say Shows how much you know. Seto chuckled and patted Mokuba on the head. "Now tell me what's going on."

And then Mokuba remembered that this was Seto's fault to begin with, and grabbed his big brother by the collar of his shirt and began to shake him vigorously back and forth. "You! You did this to me!"

"Uh," Seto said intelligently, mid-shake. "What?"

"You lied to me! Filling my head with happy thoughts when really, there is no happiness in the world. Only lies," he hissed.

Seto froze. Now, Seto had a very strict personal policy that he never lied to Mokuba. However, as he himself had to grow up so fast and cast away his childhood beliefs in how the world worked, he would often bend this no-lie rule to preserve Mokuba's innocence for as long as possible. (Such as the time he discovered Mokuba's fish floating belly-up in its bowl, and had been caught in the process of flushing it down the toilet. Instead of explaining the circle of life, he calmly explained that the fish was going on a relaxing vacation, which coincidentally lasted the exact amount of time it took for Seto to find a completely identical goldfish.)

"Is this about Mr. Bubbles?" Seto asked slowly.

Mokuba stopped shaking his brother. "What about Mr. Bubbles?" Mokuba asked suspiciously, narrowing his eyes; at this point Mr. Bubbles had taken 5 vacations and been alive for several years more than what was natural for a young boy's pet fish.

"Uh, nothing! Mr. Bubbles is alive and well!" Seto said hastily. "Until the next vacation," he added under his breath.

"What was that?" Mokuba asked.

"So what happened?" Seto asked quickly. This successfully averted Mokuba's attention back to the issue at hand.

"All these years," Mokuba wailed, fresh tears forming again, "You've been lying to me! Admit it!"

"About what?" Seto asked frantically. He sure wasn't going to incriminate himself about any of their other seemingly-immortal pets.

Mokuba began to sob. "About Santa not being real!"

A split second pause. "Oh," Seto said in a small voice.

Kaiba thought quickly. He knew that he'd have to eventually tell Mokuba the truth. He just thought that maybe he'd be able to wait until Mokuba turned eighteen. Or thirty. "Who told you that about Santa?" he asked, stalling.

"Rebecca," Mokuba mumbled, rubbing his nose on his sleeve.

"That's 'cause she only gets coal," Joey muttered flatly from his seat on the couch. "Annoying little twerp," he added under his breath.

Seto and Mokuba both ignored this.

Seto took a deep breath. It was time to come clean. "Okay, Mokuba, I'll tell you the truth," he said sadly in a heavy voice. He paused dramatically, saying a final farewell to this part of Mokuba's childhood. "Santa—"

"—is totally real!" Joey cut in. Seto glared at the blonde, who wasn't making this any easier on him by saying the exact opposite of what he had intended.

Mokuba, however, eyed Joey warily. Joey had been dating his big brother for several months now, and Mokuba liked him a lot. Joey wouldn't lie to him, would he?

Mokuba scoffed skeptically, though it sounded slightly hesitant. "No, he's not. I'm not a little kid. Don't lie to me."

Joey held up two fingers together and placed his right hand over his heart. "Scout's honor, kid."

Mokuba faltered. Whoa. This was getting intense. You couldn't just use that type of honor lightly. That was a kind of swear of trust that you didn't mess with. But he tried not to let his new hope show, and put on his best poker face. He crossed his arms and eyed Joey shrewdly.

"But Rebecca says her grandfather puts her presents under her tree. She says Santa doesn't exist."

Joey rolled his eyes animatedly. "Doesn't Seto teach you anything?" He ignored Seto's indignant snort. "Of course Santa doesn't put presents under her tree! He can't!"

Unbidden, Mokuba's eyes grew big and wide. There were limits to Santa's power? Why hadn't he known about this before? "Why not?" he breathed in awe.

Seto saw Mokuba's enthralled face, now devoid of any trace of sadness and filled with innocent wonder, and decided to let Joey continue his story. He went back to sit next to the blonde on the couch.

"Because," Joey said like it was the most obvious thing in the world. "If kids don't believe in Santa, he can't use his magic to get inside their house. He wants to give them gifts, but he can't."

Mokuba gasped. "No way!"

"Yes way!" Joey retorted inarguably, putting an end to all of Mokuba's doubts: This was real. "And it's not fair if those kids don't get gifts because they stopped believing, so their families have to do it instead so they're not left out."

"That totally makes sense," Mokuba whispered excitedly.

"It does?" Seto asked dubiously. He was promptly ignored.

"So you better start believing in him again since Christmas is in three days!" Joey warned, wagging his finger. "It would suck if he suddenly couldn't get in here after spending all year making all your gifts!"

Mokuba gulped. "I believe! I believe!"

Joey laughed. "Good. And don't let that brat Rebecca tell you otherwise."

Mokuba put his hands on his hips. "Joey, be nice or Santa will give you coal," he admonished.

Joey grinned mischievously, wrapping his arm around Seto's waist once more. "Don't you worry about that, kid." He snuggled into Seto's side. "I've got a feeling Santa's going to give me something yummy."

Mokuba tilted his head to the side as his brother turned bright red and jabbed his elbow into Joey's ribs. "Like cake?"

Seto coughed hurriedly. "Yes. Cake. Now, uh, why don't you go outside and play in the snow for a while? That sounds like fun, right?" Joey snickered at Seto's faltering ineloquence.

Mokuba's eyes lit up. "Okay, Big Brother! I'll make you a Blue Eyes Snow Dragon!"

Seto's blue eyes glowed warmly. "That would be wonderful, Mokuba."

Mokuba gave a shout of excitement and scrambled outside as fast as his legs could carry him.

Once the front door slammed shut, echoing through the vast mansion, Seto glared at Joey. "You realize this is going to make it that much harder when I finally have to tell him the truth?"

Joey wriggled closer to Seto, grabbing the brunette's arm and wrapping it around himself. He looked out the window that faced the front yard, and saw Mokuba running around excitedly in circles. "Yeah, but now he can blame me instead of you. And now he gets one more Christmas to believe in Santa."

Seto looked down at the mop of hair that was resting against his collarbone and smiled in amazement. "And why is that so important to you?"

"Because it's important to you," Joey said simply.

Seto didn't know what to say in reply, so instead he said nothing, giving Joey a light squeeze. And they both watched out the window as Mokuba played cheerfully in the snow.

So there's a little opening chapter, that's more fluff than humor, I suppose. But the next chapter should give a few giggles! I'll have that up hopefully in a week's time! If you like it so far, give a review and let me know! (I'm more prone to fighting my procrastinator tendencies and actually be productive when I know there are people who are waiting for me to get off my lazy behind and write :D )