This kinda reminds me of Touhou the game, with each part/stage being kinda isolated but at the same time not really? Well, that aside, this is pretty nice. Never thought much about pre-spellcard era exorcist, and certainly not the way this is represented.
I wonder how he feels at the end of all this, the weakling that achieve nothing even after all that, but still manage to be honored by a Youkai Sage's present,