So, I have yet to even attempt to fight Vicar Amelia, but I did find an area where I encountered one of those bag-swinging guys, and I do agree that they hit like a mofo. o.o But ultimately, they pale in terms of 'Oh Dear God' to another creature I found in the same region that... well, I'm not going to spoil the specifics, because it's fun if it's a surprise! I'll just say that their grab attack drains your Insight, and does so in such a way I am going to fondly refer to it as the 'Hentai Monster' from here on in. >.
Zanten, Doer Of The Things
Unless He Forgets In Which Case Zanten, Forgetter Of The Things
Or He Procrascinates, In Which Case Zanten, Doer Of The Things Later
Or It Involves Moving Furniture, in Which Case Zanten, F*** You.