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Kasamatsu held his breath for a moment as he looked down into the coffee mug he was holding. He’d known this day was coming, long before it did, and he thought that he was prepared. But no, of course not. No one can be prepared for something like this.
He let out the breath and cleared his throat, looking Kise in the eyes. He smiled in what he hoped was a genuine fashion and shoved his emotions down. “Yeah, of course I’ll be your best man. I’d be honored, and I’ll do my best to do anything I can to help you out.”
“Thank you so much, Kasamatsu!!!” Kise grinned, and Kasamatsu’s heart constricted at how bright and relieved it was. “I was so nervous that you’d say no and I’d have to fight Daiki for Kurokocchi!”
“Why would I say no, you dumbass?” Kasamatsu chuckled lightly. ‘I’d do anything for you.’
“Seriously, though, thank you,” Kise said, reaching across the table of the cafe they were in and patting Kasamatsu’s hand lightly. “I really appreciate it.”
“Don’t mention it, really,” Kasamatsu shook his head. His chest was getting heavier and he couldn’t blame it on anyone but himself. “I guess we should talk about venues and all that stuff. I mean, that’s what the best man does, right?”
“We’re kind of leaving a lot of the venue hunting and stuff up to Momocchi, honestly, cause she’s a lot pickier than me and Daiki. And I mean... technically we’re already married, after all, but –”
Kasamatsu’s ears started going fuzzy and he blinked rapidly. “Wait, hold on. What? You’re already married?” he somehow got out despite the growing discomfort in his stomach.
“Yeah, we already filed the paperwork and stuff. We wanted to have a ceremony too, though, for our friends and family. But we just couldn’t wait anymore.”
“When did you even get engaged?”
“Okay, that’s beside the point,” Kise rolled his eyes. “He and I were dating for how long before we decided we wanted to get married?” he scoffed, stirring his coffee absentmindedly.
Kise liked his coffee unbearably sugary, with at least five packets to start. He also liked to have hazelnut creamer but he could do with vanilla it they didn’t have hazelnut. Kasamatsu hated himself that he knew that about Kise. He hated how closely he’d paid attention to him over the years. He hated it.
But he couldn’t hate Kise.
Not in a million years.
He took a deep breath to steady his mind and shove his emotions back down. “Well, first I suppose I should congratulate you on marrying your soulmate,” he said. “And I am very honored that you’d consider me for your first choice of a best man. And if Momoi needs any help with any of the venue hunting or whatever, have her contact me, okay?”
Kise cocked his head to the side and Kasamatsu wanted to punch him for being so cute. If they were still in high school, he probably would’ve. “Okay, I will, but... are you okay, Kasamatsu? You seem... a little off.”
“I’m fine, don’t worry about me. I’ll be in touch about everything, okay?”
He waved over his shoulder as he walked out of the café, his chest tight. Now that Kise was a married man, he couldn’t really just tell him that he’d loved him for years now, could he?
It had all started when they were in high school and Kise had become the ace of Kaijo’s basketball team immediately after joining it. Kasamatsu had been pulled into orbit around Kise without a second thought, and although he thought he’d been pretty subtle about it, his third-year teammates had known.
After their lost game against Touou at the Inter-High, when Kasamatsu had climbed onto the bus to go back to Kaijo, Kobori sat next to him. “You know, Kise wanted to go back and look for you,” he said quietly, looking over at the exhausted ace that was sleeping against the window already.
“Did he now?” Kasamatsu shrugged, though he couldn’t help the flutter in his chest at the thought that Kise had wanted to go back for him. He knew Kobori could tell that he’d been crying. His eyes were red and puffy but he was just glad that Kise was asleep so he wouldn’t have to face the concern.
“Are you just going to pine after him forever, Kasamatsu?” Kobori asked lowly. “I mean, after seeing what just happened between him and Aomine, I’m pretty sure there’s something going on between them...”
“Shut up, Kobori, I don’t need your lectures right now, and I certainly don’t care about Kise like that anyway.”
“Alright, if you say so,” Kobori shrugged, looking out the window. “I still think you’re going to lose any chance you might’ve had if you don’t shoot your shot right now, though.”
Kasamatsu thought back on that time and chuckled to himself. Maybe Kobori had been right. Maybe if he’d expressed his feelings to Kise at that moment, or maybe when they got back to Kaijo, it would’ve been him getting married to the former ace instead of Aomine.
But what ifs weren’t going to help him. He had to focus and be the greatest best man ever for Kise.
It’s what Kise deserved.