I'm afraid not. The witches I know of are ones from old stories. Mythological figures, famous heroes and villains from legends.

[Hey man, she's a neutral party. u_u The Grail is her Master, not something she wants to obtain.]

... Interesting. I've never heard of such a thing... [And that's sure saying a lot. She chuckles.] Well, I assure you, you'll never find any of that around me. I'm no magus, but magic is something that I have no doubt exists.

[You know. Considering she's a magical construct herself...]