I'm sure she would think of him as one of the nobility who keeps perpetuating the sale of mana stones and normalizing the society that depends on them so she probably hates him too on principle unfortunately, but also she never meets him in her life- she basically experimented on herself so much during her life that it shortened her lifespan and she died about 300 years before current time.

She does technically interact with him in Requiem of the Wayward Scholar but by then her mana stones has been corrupted and revived by the Great Calamity, so she's kind of a shell of the person she was. At that time she sees him as being associated with Murr and therefore evil, but Rustica seeks to learn more about her even after her death and do her memory justice, because Rustica is just such a good person even to those who might hate him.