Seems holding hands with Sakura had an additional effect. I don't let the surprise show on my face and continue holding hands long after I've run out of chakra to use but before Sakura gets annoyed,
"So when do I get stronger?" Sakura asks.
"Slowly, the change is gradual but in a few weeks, you'll notice for sure. If you feel hungry, that's a good sign, make sure to eat plenty without worrying about getting fat due to it"
"I better not, or I swear I'll punch a hole in your head!"
With that, academy is over for the day and I head home to review the exciting changes.
Information seems to have been added to my head as a result of contact with Sakura, just thinking about 'ninja hormones' leads me to the knowledge of two new hormones and their effects.
I had felt those hormones within me but couldn't tell what they were before since they weren't in whatever knowledge I'd gotten from that other place called Earth.
Now it makes sense, there was never any chakra on Earth so there was no need for the human body to develop these hormones.
I'm going to call the first Chakranin. Its effect is promoting the generation of chakra.
Our body naturally generates it when we run low on chakra in order to restore the level.
The more Chakranin we have, the more chakra our body keeps generating which then leads our body to naturally develop in a way that can hold onto all the surplus chakra.
I immediately make it a priority for myself to increase my own Chakranin production. A big injection can be useful in a fight but it also costs chakra to generate it.
If it were an MMO it'd be like spending 10% of my mana bar to get a 1% mana regenerated every 5 seconds for 10 minutes, very worth it in the long run, but improving my Chakranin generation will improve both my max MP and my mp/5 so it's the winning gamer move.
As for the second hormone.
Hmm, Taijunite, Tainadrine, Leanite, Tainin, ~~Kaijunite~~, errr... I'm gonna settle on calling it Taijunin.
It's the perfect solution to my current problem. The way muscles work normally is a repeated process of growing muscle cells larger, and then breaking them into 2 through effort, more cells will result in more strength. After that, it was mostly making sure the body's bones and tendons could handle the strain and train the mind to push the body further.
That was the theory on Earth at least. In this world, we have chakra which can be used in techniques to strengthen oneself.
Normal taijutsu uses no chakra at all, and yet in this world muscles alone can let a ninja jump 20 meters high or punch a rock to smithereens without breaking all the bones in one hand.
It wasn't making much sense to me how that was possible, but only for ninjas and not regular people. It remained possible and consistent regardless of one's chakra reserves so it didn't seem like a simple chakra passive effect. A person with a lot of chakra didn't necessarily have a very strong body and vice-versa.
Taijunin is the answer. It reverses a muscle's cell division and fuses two cells back into a smaller cell with twice the density and strength. The logic doesn't seem to add up but the results do.
Now I have a way to strengthen my ladies without ending up with them looking like the staff serving an Akibahara muscle bar.
And for myself of course, while I want some muscles, I wouldn't want to have to end up a muscle freak just in the name of power, not to mention how inconvenient muscles became in too large of an amount for a regular fight. Too much surface area to protect.
For the next couple of weeks, I spend some chakra improving my own Chakranin generation. Not too much as I need to keep my cover of growing stronger physically due to contact with Sakura.
After a week I'm able to start taking advantage of the small increases in my chakra capacity pull to pull forth an even bigger increase of chakranin on myself, though each increase is looking harder than the previous.
I also notice that the harder I push hormone production at one single time the harder it becomes and the more chakra I waste preventing body adaptation.
This makes it so using all my chakra on myself is a bit of a waste and it's more optimal to focus on improving a wide range of hormone production and on multiple people gradually.
Still, it seems Hormones alone aren't enough to push me into Uzumaki chakra levels but it at least got my reserves out of "untalented tier" and closer to the levels of Sasuke and other clan descendants that have been training as early as they can.
As for Sakura, the results start to show. A healthy dose of Taijunin, testosterone, growth hormone, estrogen and dopamine are making her stronger each day, and feeling more energetic and pleased.
Sakura's combat skills don't see much improvement, my own were never good enough to teach properly in the first place, but with a couple more centimeters in height and a bit more weight in her tights and ass means her moves pack quite a punch and her Taijutsu grades raised from F to a high C in just 2 weeks.
I had to lay low on the love hormone doping during this time and focus on proving my Kekkei Genkai was real through the improvements in both myself and Sakura.