Things like Hime-sama, Denka-sama would be something that would be considered like child-speak. The same is like Wes' example. The phrase "Mister Sergeant" is weird to our understanding of English, but is also the kind of phrasing one might expect from a child who is still learning the language, and has only grasped that it's polite to refer to men as "Mister" and everyone seems to be calling this guy "Sergeant" so that's obviously his name.
The same would go for things like "Miss Princess," "Mister Teacher," etc.