[maniac88]

Originally Posted by XFire

She's from a different country (England, I think?) so she'd be of a different mythos. Though that means less and less these days.

I also recall a spoiler saying she somehow proves normal magic is useful against summon magic. Can't wait to find out how that happened....

You could see her power in the next chapter of the manga (should be)...
IIRC,

Spoiler for :

she can make some kind of mist that cover the entire area.

finally read volume 6 ch 1, and damn... A chapter full of fan services

Spoiler for :

start with hikaru doing doing something to his lower body, followed by kaguya demanding her morning kiss, some bikini show from all the girl(miyabi's swimsuit malfunction), a boat riding lesson with charlotte (in the middle of it when the tension was high Charlotte want kazuki to touch "certain place" before cockblocked by prometheus), reassuring miyabi that he will surely 'subjugate' both of them (miyabi's crying because of her 'uneasiness' being lifted), that particular scene being witnessed by koyuki which in turn want kazuki to spoil her, in the end he and kazuha went to the shrine riding the boat (cue kazuha protesting because the cockpit being so small making their shoulder touch each other, and yet her point keep increasing)