The librarian had clearly mentioned the rules of the library to Rayzen after his identity check.
" This is the library for academy students and you have to follow these rules unless you want to receive heavy punishment and be banned from the library.
1. All possessions of the library and the library itself must not be damaged under any condition.
2. If found perusing the section demarcated as forbidden, you will be punished.
3. Only books that doesn't belong to forbidden section can be borrowed.
4. Borrowed books must be returned.
5. You can read all books except the ones from the forbidden section within the library's opening and closing time. "
The rule number 2 made Rayzen suspicious. It specifically said 'if found'.
'As long as I am careful enough and don't alert the librarian, I can read those books in the forbidden section.'
Nonetheless, Rayzen didn't make an attempt, he went through other books and borrowed an D- rank jutsu, study materials for 4th year and another book and left the library.
...
Once Rayzen was home, he started studying the D-rank jutsu scroll. It was the Body Flicker Jutsu.
He easily learnt the jutsu and had a basic mastery over it within an hour. Since his foundation regarding the ninjutsu theories was solid enough for a D- rank jutsu.
As someone who watched Naruto anime, he obviously wanted to develop the body flicker jutsu to Shisui's level, but after spending time on it for all day, he couldn't achieve his aim.
Rayzen was able to perform the jutsu without smoke and basically seem like teleporting. He figured that if he could increase the speed of movement to a particular level, he could generate clones too like Shisui. But that would require that the technique be adjusted such that the chakra and body capabilities are fully utilised. Since Rayzen has more than enough chakra and his physical capabilities is in the top tier, he was overqualified for using Shisui's Body Flicker version.
As of now, the technique was enabling instantaneous movement with a corresponding amount of chakra. The more chakra used the higher the speed. But it comes with three limits:
1. Technique has a chakra consumption limit.
2. The body strength of the user is a limit.
3. Only allows instantaneous movement in a single direction.
Rayzen found that with the prowess of Sharingan and his physical capabilities, he could somewhat ignore the third limit and with practice it wouldn't be a limit anymore.
But if he wanted to generate clones he needed to improve the technique. He left it for later and went on to study the book he borrowed. The book was ' Introduction to Puppetry'.
He spent his free time at night to read the book and got engrossed in absorbing new information.
...
Days passed by and he was done with the book and started learning the fourth years study materials. And when he had nothing better to do, he would spend his time on improving the Body Flicker Jutsu.
Sometimes he got so irritated that he wished Shisui was born earlier. He found a new found respect for Shisui. Shisui must have had a lot of experience with this technique, so much so that he honed it to his name, due to all the insights he received from his experience.
On the other hand, Rayzen found the Puppetry book useful. But this was in regards to identifying all the weaknesses of older version puppets that the Hidden Leaf fought against. It also included tactics on how to combat a puppeteer as well. But the most important thing that Rayzen found useful to him was the technique to create better and more efficient chakra threads. It couldn't be said to be a technique, as it was just an advanced form of chakra control, shape transformation.
This was the key that Rayzen needed the most. Realization dawned on him, as he remembered reading through the academic texts that for creating or modifying techniques one must have good chakra control, and more importantly must master shape transformation.
With this insight, he went to the library again and borrowed books and scrolls related to shape transformation and started slowly absorbing all the information.
...
His peaceful days spent on research and study was ruined one day as he saw a crying Sora coming to him when the lunch break was half over.
" Ray... She... bullied... me! " said Sora through her sobs. Rayzen didn't ask anything and first calmed her down and like a ' reasonable person' didn't ask anything and told her to lead the way to her bully.
" Who had the nerve to bully my little Sora?! "
Rayzen cracked his knuckles as his voice took the tone of a 'retired yakuza'.
Although masked, his classmates could feel his anger and threatening aura. By this time, most of his classmates were in the class including Shiroka, Minato, Dōto, Derei and Tasu. They followed him and Sora to see the 'fun' and if possible take part in it. Shiroka wanted to calm Rayzen down, but since she was too tired, she dragged herself to witness whatever happens.
Sora lead the way to the training ground. And as Rayzen was approaching the area, he saw what he was looking for, a bully.
He saw many kids around the same number as his class assembled there and formed a circle. He observed everyone as he slowly walked to the grounds. He saw people from many of the clans he knew, even including his. And he saw a Hyuga with the forehead covered by a headband, being bullied by a another one with no headbands.
" Is that him?!" Rayzen asked in a warm voice.
" No! But... But can you help that kid from the bully too?" asked Sora with teary eyes.
'As expected of my sister, she is a kind angel! But..'
Rayzen assessed the situation and sneered as he figured that it was some-one from the main clan bullying someone from the branch clan.
He whispered to himself : " No need for me to interfere, if I do it will be worse than me walking away now. I guess this is why the branch clan hates the main one. "
And he said to Sora: " Sorry, Sora! Your brother can't do that. Its the Hyugas they have to deal with it among themselves. Besides, we are here to take care of your bully. "
His classmates were also seeing the scene. Even though everyone felt pity, none went to help, since like Rayzen said, it was the internal matters of their clan. Minato clenched his fist, being unable to do anything. So did many of them. Even Shiroka gave Rayzen a look. Like many others, she expected someone of his character to intervene. But hearing his response, his classmates were disappointed.
Shiroka sighed as she thought: ' It's unlike him! Maybe him intervening might affect his future plans. What are you planning Rayzen? And how long will you watch everything before you react?'
Rayzen was about to walk past the crowd, when he heard the rising commotion. The bully had a guy who looked to be a 20- year old with him who was exerting pressure on the kid with the headband. He heard the bully say the words : " KNEEL!"