Augh okay but imagine Jounouchi and Kaiba being single well into their late-40s/50s and everyone just assumes they're gonna be single until the end of time, only to watch as they get reacquainted and fall in love.
They're still snippy with each other but the barbs aren't as sharp, there's a warm fondness there that wasn't present when they were teens. They walked very different life paths, yet understand each other completely.
Shizuka went and got married, now her kids are close to graduating. Jounouchi is the best damn uncle this side of Shibuya! Meanwhile Kaiba struggles to be the uncle he'd like to be to Mokuba's kids, and is envious of how easily personable Jou' is with his own family. (Seto thinks he does a Bad Job, but his family actually loves him I promise-- he's just awkward lmao)
They both think the time of their lives for falling in love is behind them, so when they start to feel sparks they deny it for a long time. But Kaiba keeps inviting Jounouchi out "just to have some company", and Jou' keeps showing up. He sends Kaiba pics of things that "remind me of you" that range from goofy posters to cool ships and pretty parks. They look forward to their correspondence.
One day Mokuba calls Katsuya out of the blue while he's getting ready to meet Seto. He's wrapping up a visit at Shizuka's, and puts him on speaker so he can finish his final touches in a mirror in the hallway.
Jounouchi: Hey Mokuba, I have you on speaker, is that okay?
Mokuba: Hey! Yeah, sure. Where are you right now?
Jounouchi: I'm at my sister's. Everything okay? I haven't heard from you in a while...
Mokuba: Oh everything's fine, I just wanted to ask you... well...
Jounouchi: ... "To ask me"..?
Mokuba: ... Jounouchi, are you seeing my brother?
Jounouchi: Later today, yeah. Why do you ask?
Shizuka: Katsuya, he's asking if you're dating him.
Jounouchi: H... he's what?!? WHAAAT???
Jounouchi: N-no, we're not dating! We've just reconnected-- a-as friends, though! Just as friends!
Shizuka: Hm. See, I fully thought you were.
Mokuba: So did I! Seto has a spring in his step I haven't seen-- well, ever. And since I can't think of any particularly exciting business ventures, I thought... maybe...
Shizuka: Katsuya has new light in his eyes.
Shizuka: I dare say, he really looks forward to hanging out with your brother!
Mokuba: Ahh, that's good, I'm glad!
Jounouchi: Don't talk like I'm not here!
The call ends shortly after that, with Mokuba giving Jounouchi his blessing. Jou' of course maintains denial that it is necessary. He refuses to believe Kaiba is interested in anything as frivolous and fleeting as love, especially seeing as they've both become accustomed to being alone...
... well, not that Jou' would mind having a partner in life. And Kaiba certainly isn't a bad choice in that regard. But he knows better than to get his hopes up for something so outlandish-- Seto Kaiba, looking at him romantically? Get real.
Fast forward to their not-date that night. They get dinner by Harumi Wharf, and it takes Jounouchi a moment to sink into their habit of conversation. He keeps overanalyzing every micro-movement from Seto at the beginning, but eventually comes to the conclusion he's behaving exactly as he has been for all their other meetings. Relieved, he puts it out of his mind for now...
After the meal, they usually head back home, and often Kaiba will offer him a ride somewhere. This time however, Jounouchi allowed his impulses to take the lead and asked if Kaiba would like to walk around the wharf a bit-- and the other man agreed.
It was beautiful seeing everything lit up at night. The wharf was a popular spot on weekends, but on a weeknight it was nearly empty, which made it feel more... intimate.
Katsuya shivered when a cool breeze from off the water hit them-- he hadn't considered taking a walk before coming, and wished he had brought a better coat. Suddenly, Seto stopped-- Jou' stopped as well-- and took off his own scarf. Without a word, he wrapped it around Katsuya and tucked it into his coat to prevent more cold air getting in. Seto's body had already warmed it, and Katsuya could feel that warmth seep into him from around his neck. The heat seemed to creep up further and flush his face, too.
Katsuya: Ah... thank you.
Seto hummed in acknowledgement, but didn't pull away. Instead he seemed to lean in, ever-so-slightly.
Seto: ... May I kiss you?
Katsuya's eyes widened in shock, his jaw went slack. He didn't trust his voice in that moment, so he opted for a small nod.
Slowly Seto moved in, tilting his head so their noses wouldn't get in the way. Katsuya closed his eyes, anticipation building. When their lips finally made contact, it was like the world fell away-- no distant sounds of the city, no water lapping at the shore, no one else on earth but them. Even the chill disappeared.
It was brief, but it was everything. They didn't part right away, pressed close as they breathed and mulled over what had just happened. Seto was searching Katsuya's face for any signs of displeasure, while Katsuya's mind raced to catch up to the present moment.
Katsuya: Oh wow... so we've been dating..?
Seto: If you'd like them to be dates..?
Katsuya: Actually, those don't count.
Seto took a step back, assessing.
Seto: Hmm. Then is it alright with you if we started counting now?
Katsuya: Yes... I'd like that.
They lock arms for the rest of their stroll, continuing their conversations from before. Eventually Katsuya mentions Shizuka was under the impression they were already dating, and that Mokuba had even called him to confirm as much. Seto is so embarrassed... was he really that obvious??
Later Seto learns Mokuba has sent fancy fruit baskets to both Shizuka and Katsuya-- a sort of "welcome to the family" gesture-- and the younger Kaiba brother gets an earful for his meddling.
