Upvote:1
While I was not able to find any female demons that sound like "sarah", there is the Prince of Hell, Seir, mentioned in the Ars Goetia. The Pseudomonarchia Daemonum also does not list any demons similarly named, so it was either Seir or the - already mentioned - Succubus, though this is more like saying "The angel Seraphim", since Succubus is a collective word, not an actual name.
Upvote:3
You probably mean a Succubus. Wikipedia defines them as:
a Lilin-demon in female form, or supernatural entity in folklore (traced back to medieval legend) that appears in dreams and takes the form of a woman in order to seduce men, usually through sexual activity. The male counterpart is the incubus.
For example, this entry in the Catholic Encyclopedia indicates that one of the charges brought about against "witches" was that of "intercourse with incubi and succubi" (where succubi is the plural of succubus).