It doesn't matter even if it's the bloody high king of Gondor's son. If he's her apprentice, then her every word is the divine law. That's how it works. You'd think a Japanese author, of all people, would now that much, when in a Japanese school club a mere senpai is already a demigod, let alone the club president.
I'll drop this series is Meria is going to grovel in front of her own apprentices. Considering her status as the only alchemy master in existence, the king would throw all the dukes and counts to the wolves rather than lose her. Dukes and counts can be replaced easily, the only master alchemist in the world can't be.