"What are you going to do with that?" Kaguya asked Rei who was holding a slightly shining green gem in his hands.
Unfortunately, Isshiki only managed to last long enough for Rei to try up to three hundred thirty-two seals before he inevitably croaked despite Rei's attempts in the later trials to round the number up and reach three hundred thirty-three.
After he died, Rei's spiritual barrier caught his departing soul and sealed it in the gem Rei was holding.
"I am going to use his soul as an energy battery." Rei contemplatively said, "The sealing formation that would hide our planet will need an energy source and I initially wanted to hook it up onto my dimension but with Isshiki's soul in my hands, I no longer need to do that."
As someone more powerful than a bijuu, Isshiki's soul was quite powerful and capable of producing a lot of energy.
Isshiki's Kama technique should just dissipate a few hours after Rei sealed Isshiki's soul because the Kama marks attempts to suck Isshiki's soul from wherever it is was naturally a chakra-heavy endeavor and with his soul sealed, the marks would use up their reserves, destroying themselves.
At that point, Rei could release Isshiki's soul and it would simply return to the cycle of reincarnation.
But why would he do that?
As a punishment for the sin of living on Rei's planet for a thousand years, plotting its demise, and not paying taxes, Rei decided Isshiki would work even after his death to pay everything he owed him back.
And from Rei's very quick mental calculations, he decided that Isshiki's soul was in for at least a few thousand years of forced labor.
But after that, Rei would be extremely glad to release him, depending on his behavior. If he is a good boy and helps people out of his own volition, Rei would naturally release him sooner. Lucky him, huh?
Not that a soul sealed in a gem could actually do anything, so… sucks to be him too.
"Huh. That's... harsh." Kaguya admitted but inwardly, she was quite satisfied with Isshiki's 'punishment'. The guy did intend to sacrifice her to the God Tree, after all.
"Harsh?" Rei snorted, "He shouldn't have come to my planet with the intention to cause chaos for his own benefit here. This is my turf." He said, almost indignantly.
"He was here before you were even born, though." Kaguya teasingly reminded him, giggling when Rei's eyebrow twitched in irritation.
"Unimportant semantics." Rei rolled his eyes with a nonchalant facade.
...
Rei and Kaguya exited Rei's dimension and appeared back in his mansion where his other wives were already waiting for him, making Kaguya secretly groan because she knew her alone time with him was now officially over.
Coming in, Rei and Kaguya discovered only Tsunade and Mei lounging by the hearth in the living room and talking.
When Rei and Kaguya walked into the living room, the two women stopped talking and turned to them.
"Oh, hello. You took your time." Tsunade teasingly said, giving Kaguya a wolfish grin.
"Un. It's not nice to not share, Kagu-chan." Mei nodded in agreement, her head understanding Tsunade's words in her own way.
"Hello, girls. Where are Konan, Pakura, and Ringo?" Rei asked as he sat down in the armchair, ignoring Mei's remark with trained ease.
Kaguya too only rolled her eyes at Mei and sat on Rei's lap, making Mei pouty.
'Yes. Using my dimension as a place where Kaguya and Mei can let loose and fight to their heart's content is a great idea. I wouldn't want the tension between them to rise without any outlet.' Rei wryly thought as he observed the interaction between his two more selfish women.
Still, he didn't forget to pay attention to Tsunade too as she answered his question, "Oh, them. It was decided that Kurotsuchi's training will be a joint project between Konan and Pakura while Ringo is tending to her new apprentice Samui."
'Good. I only have to get rid of Tsunade and Mei to reclaim my alone time with Rei.' Kaguya instantly mused.
"Shouldn't you be present in your village, Tsunade? It was just recently invaded, after all." Kaguya 'innocently' asked, earning herself a deadpan look from Tsunade.
"Nah. I am good." Tsunade dryly answered and Kaguya quietly clicked her tongue.
As amused with their antics as Rei was, he had some important questions so he interrupted their bickering and asked, "Was Kumo already conquered?"
He and Kaguya were away for an entire day and by now, the Kiri army should have arrived at Kumo even if the Kiri Swordsmen didn't manage to make the village surrender.
Alas, Rei didn't have any information source while they were dealing with Isshiki so he knew nothing about what went on in the world during that time.
"Mhm. Kumo surrendered after a short siege of the Kiri army." Tsunade briefly informed.
Rei slowly nodded at that before humming, "So the Swordsmen failed, huh? Sucks to be them."
Not that he cared overly much. As long as Kumo was now under him, he was fine either way, no matter if the one doing the conquering was the Kiri army or the Kiri Swordsmen. But still...
"Kinda." Mei giggled, "Ringo only sent them because of their bragging that they could conquer Kumo by themselves and don't need anyone else. The idiots."
"Yet, here we are. Five of them are dead, and another ten are injured." Tsunade sighed. It was her who received the injured ones and was supposed to heal them. She would naturally do her duty but she would be damned if she didn't make the process as painful for those fools as humanly possible.
Rei inwardly winced when he heard his two sweethearts. He knew Ringo best and... let's just say he could imagine the punishment Ringo was going to heap on the Swordsmen for being too arrogant for their own good.
It wasn't good to be one of them right about now. Not at all...
'Alas, poor Samui would definitely get caught in this too.' Rei idly thought. There was no snowball chance in hell Ringo would not use the opportunity to toughen her apprentice a bit. 'Oh, well. It will be a good character-building exercise for her.' He shrugged, knowingly dooming Samui to a few months of training hell.
"What about Onoki and A?" Rei asked the second most important question.
As former Kages, there was always a possibility that they could cause a rebellion if they escaped and got back to their respective villages. Rei had already decided to leave them alive but despite Ringo's promise to A that she would let the man go, Rei hadn't promised anything like that.
Unfortunately for them, these two were yet another people that came under the label of 'Sucks to be them'.
"Oh, they complained and raged, demanding the seals on them to be lifted but Konan dealt with them quickly by telling them nobody but you can unseal those seals." Tsunade snickered as she remembered their flabbergasted expressions.
"But it was only after Tsuna-chan got annoyed and had beaten them up that they finally shut up." Mei cheerfully finished for Tsunade, throwing her under the bus and earning herself a betrayed stink-eye from the best and most violent medic in the world.
Beating up important prisoners of war, especially after they were promised good treatment was just a poor form.
Of course, Rei would close his eyes a bit and ignore this incident. He loved Tsunade too much to reprimand her for beating up some unimportant complaining bastards.
Seeing that there was no incoming reprimand from Rei, Tsunade grinned, "Anyway, they are both in the Village Hidden on the Other Side, awaiting you to deal with them, with their chakra still restricted to genin level."
"Good." Rei nonchalantly said but inwardly he sighed when he heard that. He was secretly hoping these two would have been already sorted out when he came back from visiting Kaguya.
Then again, that's what having so many subordinates was for and Rei was already thinking to whom he would delegate this 'glorious' babysitting duty.
Because obviously, neither A nor Onoki were leaving his village anytime soon, duh.
Leaning back into his armchair, Rei finally let out a relieved breath full of satisfaction and a smile involuntarily appeared on his face.
'At least everything more or less went according to the plan. It seems I have won the Game of Thrones Naruto-version.'