Maid of Honor

The Queen of Honor (近衛侍女(クイーンオブオナー)), also known as Royal Maid in the Baka-Tsuki translations, refers to special workers that serve the British Royal Family, as servants and bodyguards. Silvia is currently the only known named Queen of Honor, and has one of the highest ranks.

Principles
First referenced by Index to refer to Misaka 10032's "cool" demeanor, Queens of Honor or Royal Maids are essentially a type of shrine maiden because they looked after the royalty, who were traditionally said to gain their authority by having a piece of divine power. Despite this traditional role, the maids also served as bodyguards to them, having been trained in magic and interception. So strong are these Queens of Honor that they can physically restrain Queen Elizard and even worry Carissa even she had the Curtana. They likely wear traditional and elegant maid uniforms.

Finally, the maids are also well known, even in Academy City. Maids in training like Tsuchimikado Maika and Kumokawa Maria can apparently determine that Silvia is a Royal Maid just by looking at her alone.