Delphie is described as "a green eyed, zaftig woman, shorter than Wanda" with "gray-speckled black hair <...> curled up in tight locks". She uses cosmetic Signamancy spells as make-up, probably of her own design. She wears a flowery violet tunic that emphasizes her assertive chest.
Delphie seems to be in relationship with Clay Dice and warns Wanda to stay away from him.
Delphie seems to be pretending to believe that the plan for protecting the Minnow Tower from attack from the air is good enough. However, she may be hiding the fact that she has Predicted that the fall of Goodminton will occur during such an attack.
During their first meeting Wanda notices clear Signs that Delphie is in the state of personal decline. Perhaps this is a hint that Delphie has reluctantly decided to allow the destruction of her side in order to allow Wanda to achieve her Fate? She may have been forced to make this decision by her fellow Predictamancers.
Real World References
"Delphie Temple" may refer to Temple of Apollo in the city of Delphi in ancient Greece. Delphi and its temple was the site of the Delphic oracle, which was commonly believed to be able to predict the future.
Incidentally, priestesses of the temple who served as the oracle were known as pythias. The word "pythia" probably originates from Pytho - original name of Delphi, but it is also related to the verb, pythein ("to rot").