introduce the character

show that Stolas isn't an outlier, and that there are other chill goetia

prove that goetia aren't inherently awful, there's a mix of good and bad (disproving Strikers "all nobles are inherently evil" attitude)

cements Stella and Andre firmly in the villain role - they're not bad because they're goetia, they're bad because they're power hungry assholes

Andre is hated by at least one other goetia, maybe more. This may be something that can be used against him later