Some time had already passed since Rin Nohara's incident, and the small-scale battlefield between the Mist and Konoha quickly came to an end. After all, it had only been a diversion to draw Konoha's attention and facilitate Rin's capture.
During this period, Kurogane Ren didn't make any effort to investigate further.
Kakashi Hatake's situation was tragic—he had pitied him when reading the original story—but what did that have to do with him now?
Everything he did and thought was for himself.
Over the past few days, he hadn't been idle. He had browsed the exchange office and selected several Lightning Release and Wind Release ninjutsu suitable for himself.
Fortunately, he had completed enough missions. Aside from S-rank techniques, which he couldn't access, he could freely exchange and learn ninjutsu of other ranks.
Still, he understood that Konoha didn't actually have many S-rank techniques, and even A-rank ones were scarce.
After searching through the exchange, he found very few Lightning Release techniques. The only A-rank one was Chidori, created by Kakashi Hatake, which wasn't even officially recorded. As for S-rank Lightning Release? That would only exist someday after Kakashi cut through lightning with Chidori, elevating it into Raikiri.
Compared to Lightning Release, Konoha's Wind Release was in much better shape. With Danzo Shimura being a master of Wind Release, it was naturally more developed.
Though only a few days had passed, Kurogane Ren had already learned most of the techniques he found.
All of this was thanks to his exceptional chakra control, which allowed him to pick up ninjutsu with remarkable speed.
On this particular day, the sunlight was just right.
And at his home, an unexpected guest arrived.
"Jonin Minato?" Kurogane Ren stared at the man outside his door, momentarily stunned.
Minato Namikaze smiled warmly at his reaction. "Senpai Ren, just call me Minato."
"Minato… what brings you here?" Kurogane Ren followed suit and called him by name, voicing his confusion.
"We agreed before to exchange insights on sealing techniques. I originally planned to visit a few days ago, but… you know what happened," Minato said, his expression dimming slightly as he recalled recent events.
Twice now, his students had died while he wasn't there.
It wasn't truly his fault. One time, Obito Uchiha had died on the battlefield, where Minato was facing thousands of enemies and couldn't possibly keep track of his team at all times.
The other time was Rin Nohara—he had been away on a mission.
Even so, he couldn't help but feel responsible. He felt like he had failed as a teacher.
Kurogane Ren nodded, though inwardly he wanted to complain. He had assumed that offer was just polite talk—who would've thought Minato actually meant it?
Still, he didn't mind. Especially since Minato's sealing techniques, particularly his barrier techniques, were truly unique.
"Come in. You came without notice, so I don't have much to offer," Kurogane Ren said, stepping aside to let him in.
"It's my fault for not informing you in advance, senpai," Minato replied as he entered, glancing around the room with curiosity.
From the outside, the house looked rather plain. Inside… it was just as simple.
However, it was clean and orderly, and there were plenty of specialized sealing materials around, all of decent quality. Those weren't cheap.
Minato nodded to himself. As expected, Kurogane Ren was the type who didn't care about living conditions and devoted himself entirely to studying sealing techniques, just as the rumors said.
Unaware of Minato's thoughts, Kurogane Ren pulled out a tea set he rarely used and began preparing tea.
Minato's eye twitched slightly. If he wasn't mistaken, that tea looked like… the cheapest kind available.
Fortunately, having grown up as an orphan, he wasn't picky. Besides, that wasn't why he came.
After a few polite exchanges, their conversation quickly shifted to sealing techniques.
Before long, it felt as though they had found a kindred spirit, and their discussion became lively and intense.
Sometimes they verified each other's ideas, and other times they argued over differing perspectives.
Time flew by as they talked, and before they realized it, the sky had grown dark.
Yet neither showed any sign of stopping, as if they could continue for days on end.
Then, a knock at the door interrupted them.
"Hm? Another guest?" Kurogane Ren was slightly surprised. He hadn't had a single visitor in years, so why were two showing up today?
When he opened the door, he saw a figure with striking red hair.
It was Kushina Uzumaki, Minato's wife.
The moment Kushina saw Kurogane Ren, her heart skipped a beat. There was something about him that felt oddly familiar.
But she quickly regained her composure. Though curious about the feeling, now wasn't the time to question it.
"Excuse me, is Minato here? He said this morning he was coming to visit a senior."
"Kushina?" Minato, hearing her voice, finally realized that this wasn't another guest of Kurogane Ren's—his wife had come looking for him.
"Minato! Even if you're not coming home, you should at least let me know," Kushina said, narrowing her eyes. Her red hair seemed to sway slightly behind her, and an unmistakable aura of danger radiated from her.
Cold sweat formed on Minato's forehead. He quickly laughed it off. "Sorry, Kushina. I got too absorbed in discussing things with senpai and lost track of time."
As he spoke, his stomach let out a loud growl.
Hearing that, Kushina looked at both of them in disbelief. "Don't tell me you've been talking all day without eating?"
Kurogane Ren and Minato exchanged a glance and nodded silently. If Kushina hadn't shown up, they probably wouldn't have gone to sleep tonight either.
Kushina slapped her forehead. "Honestly, what's the rush? You're both from the same village—you'll have plenty of chances in the future."
Even as she said that, she felt a hint of shock. She knew Minato's sealing abilities better than anyone.
Although she had taught him sealing techniques, she couldn't confidently say she had surpassed him anymore.
And the fact that Kurogane Ren could engage Minato in such an intense discussion spoke volumes.
At the very least, his level in sealing techniques was not far behind Minato's. Otherwise, such a discussion wouldn't have been possible.
"That's true. Senpai, I'll visit again sometime," Minato said, nodding as he looked at Kurogane Ren.
"You're always welcome," Kurogane Ren replied with a smile. Through their discussion, many of his doubts had been resolved. As expected of someone who had inherited the Uzumaki clan's sealing techniques—Minato's theoretical understanding had been immensely enlightening.