Your promotion means that you can also be a private of the Queen's Guards Shrunk in an airport chapter 14 by Louka31

"I can?"

"Yes. Actually, it's a polite way of saying "must"--the Queen has been asking the Regiment Colonels for one recruit each to form a Guard Regiment."

"So what will be my duties?"

"Well, the magic of this universe means that it isn't as straightforward as in your universe with its lack of magic. You could guard the perimeter. Alternately you could be trapped in a pocket, purse, cage or table drawer for most of your days, only for the magic to call out to fight full-size when your Master needs a bodyguard."

"My Master?"

"Technically, that's the Queen but in practice she usually delegating mastery of bodyguard tinies to whichever courtier she wants him to guard."