since kiba joined the anbu .It has already a year .That day the hokage saw a huge potential in kiba , thus he said " kiba you will have permission to access to any justu and you will learn tracking and steal skill . Then you must complete some D rank quest and reach joinin chakra reserve . After that , l will give you higher rank quest after 1 year ".
But since kiba want to learn fuinjustu the most. He asked the hokage which granted his wish as there too few fuinjustu ninja in the village.
From that day , kiba start learning track , mask his chakra and learn fuinjustu . In just five month kiba learn everything and his chakra reach joinin level but he still wait after it reach peak joinin chakra level which he had achieved in two months. Thus the remaining month, he had challenged many anbu ninja to gain experience . He also create a seal name the external chakra storage ( it a seal that accumulate chakra so as to recharge the user chakra after it drain completely ) . what is the most awesome is that there is no bottleneck as the user can accumulate until one tails beast chakra reserve . This mean that kiba will not have to worry about chakra consumption . But it weakness is that there is two levels to reach . The first is that when the user must fill it himself , the second level is when it fill by itself . Thus the user must continuously drain his chakra storage and recharge it in order to reach the second realm. ( why is the the first level a weakness is that the user must refine the chakra in himself thus if the the chakra is drain during a mission ,the user will not have the time to recharge as it take at least a week to recharge . It only in the second level that there is no such weakness and it take time to reach this level).Another weakness is that the external storage will only recharge the user chakra according to his chakra reserve. Thus if the external chakra has a chakra reserve of Kage level , the user chakra is jounin level ,it will recharge until jounin level or peak at most. Fortunately ,there will be no weakness except the last one when kiba reach the second level .
He also study fire release but he had not yet become proficient with it as it consume too much chakra but he is not far from mastering it . Furthermore , it will enhance the fire destructive power by combining it with wind and also kiba was able to bear the chakra consumption due to his external chakra seal.
He also develop some wind style Ninjustu and gain a lot of experience after fighting many anbu ninja . Today is finally the day to complete a high level quest ( note the third war had already started .It was when kakashi and shishui had graduated )