I was thinking in the shower the other night, as you do, about a storyline that is all sauergeek's fault when a yet to be written character had a phone conversation with one Sister Mary Gladys. Which lead to the pondering in my head of whether Gladys is derived from gladius. (It's not by the way.) From there, while still in the shower so with no access to actual reference material, I went to the following lady (apologies to the real world St Gladys whom I looked up later):
St Gladys of Pencarrow - St Gladys was an early warrior saint of the Church in Alba and Lyonesse. She is said to have killed, at different times, a demon and the dragon who ate St Brendan of the Well. When the demon is described in any detail it is said to be an incubus.