Grammar question: Genitive case noun followed by parentheses

[Rakovsky]

How do you correctly write sentences that put phrases in parentheses between a noun in the Genitive or "possessive" case and its object?

For example:

"Superman's (a heroic cartoon figure) only weakness was Kryptonite."

The statement can be rearranged to say "Superman was a heroic figure whose only weakness was Kryptonite," but there might be some statements that cannot be thus rearranged without seeming awkward.

[Pamela]

Well,could you give some more additional statements that attach to this setence?

[Jamie (K)]

We need some examples of the type of sentence you're talking about.

It's also possible to say, "The heroic comic book character Superman's only weakness was Kryptonite."