Senjutsu

Yoruichi is continuously applying pressure on Aika's body while she ran half-naked across the training ground. She wasn't just pressurizing Aika, she's also using a healing Kidou that restores her stamina and repairs muscle tissues so she can keep running. Yoruichi is not just training her stamina and muscle strength, she's giving Aika a close to death experience so that she can get used to it that she won't freeze in face of a real life-or-death battle that she may encounter later. Although she won't push it to the point that Aika would be totally indifferent to the concept of death as that would create more problems for herself.

Yoruichi is also laying the groundwork for Aika to not to have any emotional distress and continue her top mental condition when in a fight or flight situation even if her clothing was accidentally stripped. In other words, if there is a danger and she has to choose the most optimal and efficient movement for her to either evade, defend or attack, she can let go of her shame of being naked. In short, Yoruichi is trying to make her not mind being an exhibitionist during a fight.

Yoruichi only planned to this for 3 hours as she didn't want to overtax her mind and she still has to learn how to sense Mana and Ki later, but she plans to extend this time every time her stamina improves. As Yoruichi press her Reiatsu and send some lightning strikes to Aika's vicinity, she faced Koneko, "As for you, we'll continue what we are trying to do last time. Sit down and meditate. Gather all the Ki you can and make it stay as long as possible inside your body while circulating it."

Koneko sat down after laying down a mantle on the hard floor and releasing her true form. She followed Yoruichi's instruction and started gathering Ki from her surroundings. It was easy for her at first, but it became harder and harder as the time pass because she's being saturated by Ki and her body is starting to scream in pain due to a large amount of pressure building up inside her. After reaching the point if she continues taking in Ki, she would explode and die in the process, she stopped and waited for Yoruichi's next instructions.

"Good. Now, even though you've taken all this Ki, it isn't yours and it won't follow your commands aside from letting it circulate and move it around your body. Your next exercise is to locate and separate your original Ki from Ki that came from the outside." Yoruichi instructed next.

'I could have done that while outside Ki is still in the low levels.' Koneko thought which Yoruichi somehow guessed through looking at Koneko's expression.

"Indeed, you can do this easier if it's done earlier."

'!?'

"But what you need is practice for energy manipulation. This will be a good exercise for you to control your inner Ki and outer Ki simultaneously regardless of how much of it is in your body."

'So that's how is it.' Koneko nodded while her eyes still closed.

"You'll probably need a lot of time to get used to it, but I want you to at least do it within a few seconds until we move to the next lesson, which is taming that wild horse called outer Ki for your own use."

Yoruichi already did some research on Senjutsu through Cleria's library. The information is limited but she and Kisuke understood the gist of it.

Senjutsu is the power to control the flow of life energy or ki in living beings. Using it, one can strengthen both their internal and external bodies or even cause vegetation around them to bloom or wither. Senjutsu users are able to sense the Ki and auras of others thus letting them track targets from far away distances. Through disrupting the Ki of their opponent's ki or severing it, it is possible to cause direct damage to their spirit and using this as an attack could result in killing their opponent. As such, there are very few ways to defend against Senjutsu.

The most basic method of learning Senjutsu is through meditation by concentrating on their state of mind and to quietly release their own or inner Ki as well as to sense the natural or outer Ki of their surroundings. It is also the best way to develop one's skills in Senjutsu.

But Yoruichi and Kisuke were confused as to why Senjutsu users are only utilizing their inner Ki strengthen their bodies and to somehow control outer Ki from the outside and not taking it in for their use.

Both Yoruichi and Kisuke experimented with it and surprised at their findings. Using outer Ki directly will cause the user to lose control of themselves and enter a berserk state. Now the two of them knew why nobody tries it, or maybe someone else had done it but lose any form of rationality from too much use. But Kisuke isn't discouraged, on the contrary, he felt ecstatic as the berserk state from using the outer Ki is very similar to when a Shinigami or a Hollow removed the boundaries on their Reiatsu and gaining the power of each other. Notably in Shinigami's case where they have to control their inner Hollows to make full use of its power.

Although the berserk state is a cause for concern, it wasn't able to stop Yoruichi and Kisuke to pass this method to Koneko as they will help her control it. It's a small price compared to the power she will gain and Koneko trusted both of them, so she accepted and agreed on learning it when Kisuke proposed it to her.

The Senjutsu skill that Koneko will learn is to draw the outer Ki inside of them, blending it with their own inner Ki. This adds a new dimension of power to the practitioner's Ki, resulting in the creation of a more powerful Ki that is very close to nature.

After three hours has passed, Yoruichi stopped tormenting Aika, and Aika regained her bearing. Remembering the traumatic experience earlier, she started shouting obscenities which dumbfounded both Yoruichi and Koneko, making the former laugh out loud.

As Yoruichi is teaching Aika how to sense Mana and Ki, and Koneko has some success with her training, all of them felt a sudden pressure that came from the distance. Yoruichi snapped her head towards the place where a massive amount of Reiatsu was being released. She knew that something has gone wrong, 'Kisuke!'