Noble society is stratified to near-ruinous levels, and it's almost all down to how much mana you have and whether you were born a lay-, med- or archnoble. Tea parties are a big fucking deal: you don't want to be summoned by a noble higher than you, because you cannot refuse, you have to do what they say and the higher-ranking one should recognise the imposition, but often doesn't. For instance, Rosemyne nearly causes a national incident when an ignorant prince demands she tell him how to talk to a girl.