Cornelia-17 is a cranky but kind intelligent computer that runs the Decrepit, Moonshadow’s space ship. Her digital resources include the Celestial Yellow Pages.
When Moonshadow takes the ship and crew into dangerous territory, Ira tries to take over the ship and get them to run away. Cornelia-17, loyal to Moon, refuses to let Ira take control.
Moonshadow later loses his ship, but it is returned to him when he joins the Machovian army, and Cornelia-17 is happy to have him back.
However, Moon once again loses the Decrepit, this time to intergalactic car thieves, who remove some of Cornelia-17’s logic circuits for salvage. Thereafter, Cornelia-17 is somewhat loopy, and speaks in rhyme and song. She remains, however, a loyal friend to Moonshadow on the rest of his journeys.