From SuspireWiki

Is the best of the best when it comes to protection. The Thegn is tasked with protecting the King, he is his constant companion and tends to follow and watch the King were ever he may be. It has been rumored that the two share sleeping quarters to ensure that the Thegn is there in case someone is crafty enough to slip past the defences into the Kings chambers. The Thegn is under a Full Viniculum, Fully Conditioned, under what has been rumored at least 100 years of Entrancement, Multiple Oaths, Mind is constantly read by the King as well, to ensure that the Thegn is fully loyal to his King, some whisper the Thegn is nothing more than a lapdog to the King, while others see him as an attack dog, on the rare occasions he does disappear from the kings side for a year to go seek out someone who the King wishes to be eliminated.

The Thegn not only is the best of the best when it comes to all things Martial, he also needs to be an expert in Auspex, and keen on the small details around him and his King the slightest change could be the difference between a failed coup attempt and ushering in a new King of the Americas