inside an old relatively big wooden room , 55 children who exactly look the same can be seen . these are ren and his shadow clones while the mc himself is sitting on top of his small bed laughing uncontrollably but in a low voice . ren is too happy because he can actually use these magical techniques especially the shadow clone jutsu which is one of his most favorites.
finally when the sky outside became dark , ren managed to calm down a little and his laughter stopped but joy could be seen in his sharp eyes as he looked at the shadow clones who seem to have somewhat different personalities. ren wasn't bothered because he knew about this phenomenon from anime and practically could not care less about it .
( mc POV )
fuu.. in this life I'm not that handsome but still seeing so many same faces is really magical . anyway , looks like my conjecture was right . each of these clones has half of the peak academy level chakra which this body possessed and my own chakra hasn't depleted at all and I of course dont feel any exhaustion . but I will not get complacent now because somehow I intuitively know that if I release all these clones at the same time then I will definitely become mentally crippled which I dont want to try at all .
hmm.. there are 54 clones in total but this number is only coincidental because I just flared my chakra before randomly but now I pretty much know how much chakra will be exhausted ( in my case no exhausted) everytime I make a shadow clone . still it's good because i can now make as my clones as i want . its like my body remembers the chakra amount which is an excellent thing because I definitely dont want to waste my brain power excessively every time when casting a jutsu .
( 3rd person pov )
ren being a practical person was still excited but knew that time was of essence . he rounded up the clones and assigned them their duties.
a group of 25 clones were assigned to practice leaf chakra control exercise as ren remembered from the memories that previous owner practiced this technique very rarely so his chakra control could still be improved very much after mastering this exercise.
another group of 25 clones was assigned to practice chakra strings . ren didnt hear in the anime but he knew that this technique was considered a difficult and versatile one. so he figured that with improvement his chakra control will also improve very much quickly . right now ren could only manage to produce one thin strong 7 cm long with enough focus but he knew that this technique wont be much difficult for him . the reason being simple because ren figured out that his concentration and mental power was much stronger than the previous owner . he didnt think much and figured that this must be another of being a reincarnator so his soul may be stronger than others.
the 5 left rens including the real one were reading the beginner fuinjutsu book in parts . ren didnt want to experience much mental stress so he limited this job for only 5 . as for two other tasks ? the clones who grasped something or performed better than others will immediately release themselves and the experience gained will be transferred to ren . this way ren can cope up with the mental stress that comes with excessive information from clones . now ren only hoped that he can become strong quickly because with him becoming strong like from genin to chunin , his soul will also become much stronger. then his improvement and comprehension speed will skyrocket.
the previous owner's limit was sticking 5 leaves on his forehead which was too sloppy for an academy student studying for more than three years. so with ren's strong comprehension , the improvement was much faster too . all the 25 clones could stick 9 leaves in average on their first try and the most efficient clone could stick 13 leaves . this showed that even though ren was a newbie but with all the experiences of previous owner and his strong comprehension, his talent was very good .
then for next five hours ren continued studying the book while trying his best to remember the crucial points. ren was amazed because with his intelligence he could tell at a glance that most of the information in this book was crucial. this discovery made ren realise again that he was lucky to have mito as his teacher otherwise ren would have to first search for books on fuinjutsu which would take a lot of time and effort . then he would have to waste too much reading the books because of finding the crucial information while discarding the useless one. this process would have taken months and for only beginner fuinjutsu at that . so ren felt truly grateful to mito and decided that he would try his best to answer her expectations. ren wasn't an idiot so from mito's interactions he could tell that he had excellent talent for fuinjutsu . so why would he not practice it then ?
in those five hours clones dissapeared at uneven times but fortunately there was a little interval among them . ren finally experienced the mental stress and the joy of gaining experience but strangely he didnt feel any uncomfortable. ren decided to blame it on his cheat infinite chakra and strong soul now and would think about the reason later when he had time.
in the end ren's body was still that of a child so he involuntarily fell asleep when all his clones released. but he had a distinct smile on his face because his chakra control already reached mid genin level from Jack shit in just small amount of time . of course ren knew that further improvement will become difficult with further advancement every time but now he decided to savor the satisfaction he was feeling honestly ....