Kakashi and Obito were in Kamui for quite a bit longer than anyone expected. Minato had feared the worst, but, amazingly, both his students had returned alive. They had superficial injuries, and Obito looked rather shellshocked, but otherwise they appeared no worse for wear. Minato hadn't really expected that.
Apparently, neither had Madara or that plant thing, Zetsu.
Kakashi had yet to explain, but something monumental had happened in the other dimension. In any case, Obito changed sides and the tide had turned in the war.
And then, soon after, it was over.
Kakashi and Obito were the only ones missing again, back in Kamui. All Kakashi had said to explain before they left was, "Obito and I need to discuss something privately. We'll be back in ten minutes."
Ten minutes, of course, had turned into nearly an hour. Awkward waiting dissolved into amicable chatter between the still-standing shinobi. With no battle to focus on, Minato flittered about anxiously, mostly around Naruto, until his two students finally re-emerged from Kamui.
"Kakashi, Obito? You're alright?"
"Maa, yes, sensei," Kakashi answered as he readjusted his crooked mask. He was limping slightly. Obito tried to smooth wrinkles out of his torn pants as he studiously avoided Minato's gaze.
Minato narrowed his eyes. "You two weren't fighting again, were you?" he asked, ready to scold his students as if they were thirteen instead of thirty.
Kakashi blinked slowly. "...No, sensei. Not exactly," he replied in a too-amused tone.
Obito seemed to think the ground looked incredibly fascinating.
The pieces clicked into place and Minato's eyes widened. Oh. Oh.
Naruto, his innocent boy, looked completely lost. "Huh? What? If you didn't fight, what did you do?"
Before anyone could stop him, Kakashi eye-smiled, curled an arm around Obito's waist, and said, "Why, I employed the power of love, Naruto-kun." He paused for effect. "Repeatedly."
Obito looked like he wanted to crawl into a hole and die. He instead tried to punch Kakashi in the head. "What the fuck are you doing, telling him that!"
Kakashi managed to dodge while still holding onto Obito. "But it's the truth, Obito. Even Rin approved. Don't deny our love!"
Obito hissed through his blush, "I'll show you love, you asshole!" as he attempted to get a laughing Kakashi in a chokehold.
"You know, this is just like chapter 12 of Icha Icha Vio—ow!"
"Huh," Naruto said as he watched the two tussle like Academy students. He wriggled the bandaged fingers on his right hand and turned to holler at Sasuke, "Why couldn't we have just used the power of love, teme?"
Sasuke, blank faced, tipped his head thoughtfully. "...Hn. We still could. Later tonight. Just to make sure."
Naruto grinned, "Repeatedly? Just to make sure."
If only Jiraiya were still alive. Minato would kill him again.
The scuffle had petered out with Kakashi and Obito both sprawled on the ground, Kakashi whispering in Obito's ear. Obito turned beet red, sat up, and said to everyone, "We'll be back in ten minutes."
As his students disappeared back into Kamui again for god knows how long, Minato sighed. As happy as he was for all of his kids, he did not want to know the details.
Make love, not war, indeed.