So then she would be the healer, just not for the masters
Like I said, her magic isn't particularly suited to healing. Also, servants don't really
need healing, usually, and that would also require them to involve her in the story at an earlier point.
She's probably better at hurting servants than she would be at healing them, honestly. Her magic is pretty good at that, although it's obviously restricted by the fact that she's up against a Heroic Spirit....