I wanna ask something, as I found no more detailed info about this in other topics. I came here looking for an explanation on Iruka Y+1 passive, that states that 15% of nin is stacking each time until his action. My questions are:

1. Is this a non-removable buff, which dissapear from the battlefield when Iruka dies? Or is this a type of "scaling" for all the team?

2. If, for example, a ninja modifies the stats (i.e. Kushina [Red Hot-blooded habanero] ), he buffs +15% nin of base nin taken from that ninja, or from the actual stats?

3. Related to the above question: is iruka buffing 15% of himself's Nin to the other Konoha ninjas?

Thanks, it may clarify me wether to use Iruka or not in scaling teams already.