Pathfinder Bushi archetype courage Bushido question

[Railak]

What counts as a magical fear effect? Would a dragons frightful presence count as a magical or non magical?

[Resileaf]

Magic fear effects come from magic or spell-like abilities. You need to look at the source of the magic on the creature to know if it matches.
As far as dragons go, their fear aura is 'extraordinary', which is not magic.