This is probably the best article I've seen regarding the oft-criticized Sorceress's design. The gist is that she's a necromancer and the artist chose to associate her ability of rebirth of the dead with classic fertility goddess imagery.
This is pretty baseless speculation, especially when there are much more likely reasons for the Sorceress's design.
First, fertility goddesses generally weren't just associated with large breasts, but large frames in general. This isn't surprising, since fertility in agriculture means eating well. Fertility goddesses also tended to be associated with childbirth and therefore pregnancy.
Second, the article acts like the necromancers are the only ones in Vanillaware games with large breasts, when large breasts can be found on many other female characters who most certainly are not necromancers or references to fertility godesses. So if large breasts are the connection between necromancers and fertility goddesses, why are they found on other characters who aren't necromancers?
Third, there is zero evidence for the connection made between necromancer and fertility goddess beyond "they have large breasts". Sure, there are a lot of obvious mythological references in Dragon's Crown, but those references are
obvious and have much more to back them up than "they both have big breasts". Arguing a character who is
half-skeletal is a reference to fertility goddesses is going to require a hell of a lot more than "they both have big breasts".
Fourth, the Sorceress's status as a necromancer is one of the less prominent parts of her character, so the idea that it dictated the most obvious part of her character design makes little sense.
Fifth, there are much more obvious mythological inspirations for the Sorceress's design; for example, the old ugly witch who uses magic to appear young and beautiful. In fact, that's exactly what the Sorceress is implied to be depending on how you interpret the skills menu. Or for another example,
the common trope of hot witches.