As posted above, their designs are clearly imitating pre-pubesence with the exception of their sexual features - which in itself is really worrying. We're talking overly large eyes, petite hands, reduced lips, rounded faces, small figures, and so on. I mean, seriously, look at Aquamarine's post. That just isn't what high school aged girls look like. The show revolves around their relative whimsicality and immaturity - drama without actual drama. While there is never any situation that actually requires an protector in the show (hence the "without actual drama"), if you were to transpose them into a real life situation, which is how much of the fan-base likes to imagine them, it's quite clear they'd require someone to provide protection or guidance or they just wouldn't function.