I think Imoko is like pre-Flanderization Ned Flanders. She's perfect (which causes no end of stress to Neeko for being compared to her, since as the older sibling, she's supposed to be the one who's leading her siblings on by example), and a part of that perfection is both an undying and even unquestioning filial respect for her older sibling and a humility that means she can't even see the relative social value placed upon what she does compared to what her older sister does. (Just like Flanders's perfection meant he couldn't either recognize how terrible a neighbor Homer was, or how much he drove Homer up the wall by being so perfect.)
