Curtana can kill Aiwass

That sword was an extreme spiritual item that fully unified the three factions and four
regions of the United Kingdom and that could draw on a portion of Archangel Michael’s
power while on UK land. If a qualified user released that power even for a moment, a
swing of the sword would sever all dimensions at once and giant ruined materials would
be created along the line of the slash.

Yes, all dimensions.

Assuming it could hit, that extraordinary power could penetrate the barrier between
worlds and kill a being lurking in a different phase...for example, Holy Guardian Angel
Aiwass who stayed in the layer of physical laws at the very bottom.

-Shinyaku Toaru Majutsu no Index Volume 22 Reverse Chapter 4 Part 7