Naruto-The secret sage

"I understand but I have a question. Why not spread sage mode since you clearly can? Surely having many sages would help the village greatly so why not?" Kakashi asked seriously.

I sighed and shook my head "You are misunderstanding something. You are looking at sage mode as if it were merely another technique like the [rasengan]. The truth is not so simple. Sage mode is a dangerous crutch if someone without enough power to begin with learns it. It's something meant to enhance what is already there, not serve as a power onto itself. You already come close to S rank and thus have a plethora of things to be enhanced, the rest don't." I explained seriously.

"So in the long run it would do more harm than good for the village." he said with a look of understanding.

I nod "It would kill or at the very least cripple the potential of those who shouldn't have learnt it had I not existed. Chunin would stall at Jonin when they may have become S rank and so on, it's not a future I like very much." I said honestly.

"I see. Lets move on to training then." he said dropping the subject.

I hum in agreement "Lay down or you'll fall over once we start. In addition you need to eat this nutrition pill and bite down on this so you don't break your teeth from the pain." I said as I took out a rubber gag and specially prepared food pill.

There was nothing kinky about this gag however but rather super serious as a shinobi's muscles were just that much stronger than a normal persons and if Kakashi were to clench his teeth as hard as he could because of the pain he'd shatter his teeth if there wasn't something to stop him from doing so, hence the rubber gag.-

The silver haired ninja understood this and stuffed the gag in his mouth as he laid flat on the ground. 

'Sage art: Natural furnace!' I thought as I slammed my palms into the floor of the chamber.

Immediately the crystal of the floor began to creep over Kakashi's body until the entire thing save his face was covered.

"Brace yourself!" A say urgently and his visible eye narrows in concentration.

Seeing this I start forcing his crystal enclosure to be filled with more and more natural energy.

With nowhere to go as I prevent it's escape the energy grows denser and denser until it's forced to press against his body and into it. The rubber gag creaks as he clenches his jaws in agony but I had to give it to him, he didn't scream. I focus my entire attention on him keeping his body from fossilizing despite the sheer volume of natural energy contained in his body. At first his chakra fights back against this malicious invader but soon the shinobi energy worked to heal the damage being done to his body instead.-

Old cells were killed by the nature energy and replaced by new and slightly more resistant ones in a full body cycle teetering dangerously close to the edge of catastrophic failure. This process lasted a total of five entire days nonstop but the pain thankfully decreased as time went on for him until he was feeling only a slight itch all over his body. This was where the food pill came in for him as it kept his body from keeling over in starvation but it was a close affair.-

I pushed my palms against the crystal encasement and with a flex of my sage chakra caused it to turn into sand that fell to the side of his body. The rampaging natural energy immediately fled from him into the air to disperse as a result. He was out cold the moment the pain and pressure vanished and I carefully examined him with my medical jutsu as I removed the rubber gag that was covered in stress and pressure cracks. Besides severe nutrient loss and weakness in his body from muscular hypotrophy or loss of muscles he was better than fine.-

His cells were practically humming with vitality as a side effect of his natural energy treatment and once he recovered he'd be ready to attempt sage mode. The only reason he hadn't subconsciously entered the state during this time to begin with was because I refused to allow the natural energy to fuse with his chakra or it would have ruined the entire purpose of this treatment. I gently picked up his unconscious form and flickered out of the chamber and out my my house while heading straight to the hospital. I moved so fast through the village that the few shinobi who could perceive me broke out in cold sweats.-

When I got to the hospital I wasted no time at all appropriating a room for Kakashi and hooking him up to a nutrition solution. The doctors in the hospital went to throw a fit about it until they saw that it was me that did it and immediately turned subservient. 

"Keep the nutrient solutions coming when he runs out and after he wakes up he is to eat high protein and fatty foods only for the next three days." I commanded and the doctors wrote it down seriously.

Once that was done I flickered away with my sensei's office being my next destination. I didn't go straight into her office but reported my visit to the secretary who then told her. I was then quickly called up by her and entered her office properly.

"You smell like you have been sweating heavily and not bathed in days. What happened?" she asked concerned.

"I spent the last five days nonstop conditioning Kakashi's body to natural energy. He is currently in the hospital recovering. I assumed you'd want to be informed of this immediately which is why I am here." I said seriously.

"The hospital? What exactly did you do to him that would require that?" she asked both concerned and curious.

I saw no reason to lie to her and told her in detail how I forced Kakashi's body to forcibly adapt to natural energy.

"By the sage! You could have killed him!" she yelled angrily.

I shook my head "I always made sure to keep the damage above that threshold, he was at no risk of death or even crippling." I said calmly.