Keturah

It's the name of the titular character of Keturah and Lord Death. That Keturah is a beautiful storyteller who persuades Death to spare her life for one day by promising to tell him the end of her story. The story is about true, undying love, and Death also adds that if she finds love of this kind by the end of the day, she'll be allowed to live til old age. You'll have to read it to find the ending. ;-)