Is this a fan fiction? Cause if it is then it's really well done, and if it is a collection if grimiore cards that I've just never read before then I think the 'angel' could be the Gardener that is mentioned in Rasputin's grimiore card, because the gardener was defeated by the darkness, and the vex took her place in the Black Garden, which would explain her hatred of machines, because the vex have taken the Garden from her. But anyway, I don't know if this is even grimiore cards or just really impressive fan fiction