Things were not simple with Orochimaru and before they could continue with anything, the two spent the better half of the day discussing their cooperation instead of actually collaborating. It was clear to Kai that Orochimaru, in his goal of learning every Jutsu, had shifted his attention to Fuinjutsu, and given his attempts at forming a seal that interacted with souls, Kai could somewhat understand what Orochimaru was trying to accomplish.

In return for Kai's Fuin expertise that was only an Adamantine Sealing Chains away from trumping Kushina's talent, Orochimaru would assist Kai in the proper utilization of the special enzymes to form a gateway to master Senjutsu Chakra. Yet, it needed time. Orochimaru certainly wanted to do this in a secluded location that did not give away the location of his other facilities.

As such, after their discussion, Kai returned to the Senju compound and trained like usual. Aside from Senjutsu, Kai was also interested in Yamanaka Clan's techniques. He felt that the secret to their skills lay in a more unorthodox application of Genjutsu alongside the utilization of the concepts of spirit body studied by the Uzumaki Clan.

At this moment, while Kai agreed that Orochimaru could be dubbed as the strongest one around... it was mostly out of the 'hype' from Senjutsu Chakra. After all, the only one to truly master this state was the First Hokage who leveled an entire region in battles alone.

If Kai had to be practical, he felt that his own chances were great. Sure, his chakra was relatively on the lower side but... the sheer arsenal of skills he had could catch anyone by surprise.

'Now... I should also think about developing a better way of utilizing these skills,' Kai narrowed his eyes. He couldn't hope to use all his skills even with Shadow Clones due to the high chakra demand. Instead, he wished to select the strongest and most efficient methods and tactics to deal with opponents.

After all, the strongest shinobi are the surviving shinobi and the only way to survive is to make sure that the enemy never gets the chance to show their full strength.

He needed to be the quickest and deadliest.

As such, that's what Kai started to focus on with his clones 'Grinding and Chill' like usual in a sealed Uzumaki Training ground. After all, this world will be in true danger if his clones are let loose easily...

---

Mikoto had gotten used to waking up by being sandwiched by a really clingy tomato and even clingier short beefcake but feeling the distinct lack of something warm and stiff against her back and a pair of thicker arms around her waist. The year had allowed a lot of inhibitions between Kai and Mikoto to shed including Kushina. So, when it was Nono who was spooning Mikoto from behind, the Uchiha felt uncomfortable. After all, Nono was somewhat shorter than Kai and Mikoto and couldn't necessarily act as the big spoon.

Groaning and sitting up early in the morning, Mikoto looked genuinely confused and sleepy. It wasn't like Kai to miss out on sleeping with them when he employed shadow clones for his grind.

Waking Kushina up to question her would be an absolute mistake since the sleepy redhead was not a morning person. She quickly noticed a note set on the nightstand towards Kushina's side and pulled herself out from the middle only for Kushina to quickly roll over, latch, and slobber all over Nono...

'Oh, my god, he is actually making good progress on his 'dreams'...' Mikoto realized. After all... there were already three of them and if they included a very endearing Tsume who accepted Kai as beta... then things were certainly looking 'brighter' for the Jonin not present here.

Shaking herself out of these thoughts, Mikoto skimmed through the note.

— Hey, so, it was really weird. I mean, I really needed to drink milk and we were out of it. Now, Sensei wouldn't share hers so, I'm out finding milk.

Of course, Sensei knows where I am. I'll be back quickly... I don't know. I think the possibility of death is quite real. Just joking. Am I? Go figure~!—

Mikoto was dazed for a second before she frowned and scratched the back of her head. Yawning, she slumped on the bed beside Kushina and slept away while turning to face the redhead.

As for Kai, his cryptic messages, and the thought of him dying could be dealt with an hour later once Nono finally wakes up and brews a fresh cup of tea.

---

"To think you would have an unsanctioned laboratory in the Forest of Death... remind me why I shouldn't rat you out to Sensei?" Tsunade inquired as she stood in front of a large nutrition tank filled with pale yellow liquid within which a naked figure floated. His short black hair floated up while the figure kept his eyes closed.

But Tsunade wasn't alone in the dimly lit laboratory as a raspy but feminine giggle filled the lab, "There are plenty of reasons not to do that. Most prominent of them being the fact that I will not go down easily and it would unbalance the structure of the village. It is better for Sensei to remain ignorant on some matters... and the other reason by itself is your knowledge of Kai-kun's actions... hehe, it would seem that Jiraiya, despite his addictions, is the one who is really making Sensei proud, huh?"

The fact that Kai went to Orochimaru wasn't hidden from Tsunade. He did not need to hide it in the first place since this was a transaction. For reason well within Tsunade's capabilities to imagine, Orochimaru had a greater insight on many things Danzo was researching in the beginning... but for her own peace, as SHE just stated, Tsunade decided not to probe the subject and feigned ignorance.

Indeed, Tsunade did not like human experimentation and it was one of the reasons why it took her so long to develop the medical ninjutsu but that did not mean that other villages or even Hiruzen shared such inhibitions as long as the 'subjects' used in experiments were none other than enemy nins.

And, Tsunade knew that even if Orochimaru and Kai did not mind her addition... her morals mattered very little in the situation. She had nothing to do with this but she was quite stubborn to tag along to make sure of Kai's safety which opened her to a lot of teasing from the youth set in the tank and...

A pair of pale, chalky arms tenderly held Tsunade's shoulders from behind through the darkness as a raspy purr grazed her ear with a pair of glowing yellow-slitted pupils revealing in the darkness, "Don't you worry about him. Such... concern, robbing the cradle, are we?"

"Keep running that mouth of yours, I'll be robbing everything you worked for the past years... but to think the Snake Sage screwed you up in such a manner is hilarious. Ah, I see. Jiraiya will love it," Tsunade smirked as she practically felt Orochimaru's frustration from behind.

"Let's keep it between ourselves, shall we. It still surprises me how only you were the one in the whole village to find it out in a single day. And to think I had great expectations from your Legacy Guardian..."

"Well, not everyone considered shifting their body structures in such a manner. I would actually love to see the report on your changes..."

Only a giggle replied to her, "You would, wouldn't you? Maybe you can share one of Senju Legacy Jutsus? I would love to see it, too."

Tsunade scoffed, "You know that I will eventually work up on Danzo's research."

"In years, yes. I never doubted your intellect. But to match my pace, you need to make the necessary sacrifices."

Tsunade grew silent before exhaling a short sigh, "No. Not me. Ever."

"What's a human experiment if not a patient with an unknown ailment?" The voice countered.

"Is that what you tell yourself every night?" Tsunade frowned.

"Oh, Tsunade... I don't tell myself anything at night. I just... make the best use of this body then, hmm, in a more primal manner. I truly find myself admiring your mental strength, it can be incredibly lonely."

The pair of lips next to Tsunade's ear was a shy away from pecking her but pulled back with a flirtatious huff as the busty Senju rolled her eyes, "You really lost a few screws after adapting to the Senjutsu Chakra, huh?"

"On the contrary, I need a rather... admirable screw now more than ever. But not many ever caught my eyes... how lucky you are cannot be put into words." With that, the pair of yellow-slitted pupils turned to Kai floating in the Nutrition chamber. The moment Tsunade decided to accompany him, he readily agreed and even let one of his clones transform into one of the rubber bands tied to Tsunade's pigtails. The Clone was... absolutely freaked out by certain revelations in the dark, but again, he felt fortunate that he didn't need to deal with it.

Poor Original Kai, the clone shrugged.

"How long?" Tsunade questioned.

"There are two ways, that I deduced to introduce this special enzyme on Kai-kun. The first one is... almost primitive. I would inject Senjutsu Chakra into Kai-kun with a bite similar to how the White Snake Sage works. Of course, pure, unfiltered Senjutsu Chakra will be injected and laid down as a seal formed from the enzyme itself. Why I call this primitive is because Kai-kun, for the better half, will represent those monstrous buffoons blessed with these special Kekkei Genkai. In essence, the Senjutsu Chakra will eat on the user's mind and ail them as it did me once."

"And the other method is this?" Tsunade frowned.

"You need to relax. Kai-kun may not boast your insight but I let him through a good amount of this research to assure him. In fact, there is a precedent already."

"What do you mean?"

"Danzo has one 'product' who can use Senjutsu. Of course, that... infant," Tsunade's body shuddered and she bit her lower lip, "was sent outside. If anything, keep in mind that Danzo won't give up so easily. He believes that Hokage is his rightful position... the fool."

Orochimaru added, "And before you ramble about how I did 'bad' things. It is because of my actions, that Kai-kun can have a safer transition."

Tsunade knew she was a huge hypocrite and her silence announced that very fact loudly. She couldn't rebuke. Morally, she was disgusted. But even deeper, she came to a sick realization that she felt relieved and helpless at the same time.

"This method is more special. In essence... Kai will be granted a gift. Of course, not many can accept it. The previous one was a success because that boy was spliced with the dna of snakes from Ryuchi Cave. This time, I had to opt for a different method. See those seals?"

Tsunade looked at the seals engraved on the surface around the Nutrition tank as Orochimaru pointed out, "That's where the magic happens. The enzyme in the tank will fill Kai-kun's streams and that seal will attract nature energy around us. Of course, I still have to be present to mark Kai-kun with a cursed seal as a point of entrance for him to start absorbing the nature energy later on but as you can understand, I managed to develop this method which... grants a Kekkei Genkai to other stronger individuals."

"Both of your Sage Modes will be different then?" Tsunade questioned.

"That is likely. Mine is complete. I studied this enzyme to perfect my situation. Kai-kun will take upon this enzyme and... well, become someone with a Kekkei Genkai. Both of our methods have their own advantage and disadvantage but it won't be an ailment to either of us."

"And what happens when others find out that you formed a method that blessed Kekkei Genkai?"

"It will be considered Forbidden Knowledge, of course. Sage Mode is linked to your Grandfather so this may even incite a war. But if I am to be honest, it is just one of the things that will remain as my legacy. There are so many things I need to master that despite the benefits, Sage Mode is a more convenient tool to accomplish my goals."

Letting out a wry smirk, Tsunade shook her head, "Man, you and Kai are crazy."

"Great minds think alike."

Scoffing, and knowing full well that Kai was on her hair, Tsunade crossed her arms under her assets, "Great minds? Both of you are bimbos for knowledge and strength. Kai with his dream of harem... and you with your weird and questionable decision. How is that the act of great minds?"

"Well, only great minds can empathize with each other. You wouldn't get it Tsunade."

Realizing she'd been called a fool on the sly, Tsunade growled but the next instant, the right band on her twin tail dispersed with a plume of smoke and let her smooth blonde hair fall over her back while Kai's body within the tank began to shudder.

"Hmm, and what was that?" Orochimaru smirked.

"I dispelled my clone," Tsunade replied with a straight face even when they knew what was up. Yet, both of them observed Kai's shuddering body 'grow' further.

His skin darkened rapidly before even darker scales began to form around his forearms as the flesh around his forehead hardened and grew into two, small but sharp horns as cracks began to develop on the glass of the nutrition tank. The Seal on the ground worked continuously, absorbing an enigmatic force from around him.

It wasn't long before the cracks in the glass chamber spilled the pale yellow liquid that evaporated after coming into contact with the surroundings.

A haunting chuckle filled Tsunade's senses whose amber eyes were wide in surprise as she saw the 'thing' in front of her with a noticeable blush creeping up her cheeks, "The most impressive, right? Want to know something else? If Kai masters this state, he can theoretically stay in this state forever but that's a realm of mastery that even I have yet to achieve."

"Shove it," Tsunade turned around, "It's a success so no need for me to waste my time here."

"Oh, and I was hoping you would stay and help me test Kai-kun~!"

"Keep it in your panties, Bimbo," Tsunade snorted, "Do anything stupid and I will make it my mission to hunt you down, Sage or not."

"Hmm, I look forward to it." Orochimaru matched the challenge with a smirk as Tsunade only felt annoyed by the 'silhouette' of the Snake Sannin through the darkness.

If nothing else, that silhouette itself posed an extreme challenge to Tsunade.

***

Shoutout to Christian, Joseph Bibb, Ocean Breeze, and Rakeido!!

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