Noble caste

Inheritance
To be an "heir" is not a caste-rank. As subtle as it might be, there is individual choice in this society: the head of household's choice, in this case, of whom to appoint as heir. Sometimes, there are mistakes.

Being poorly suited to run a household does not mean an heir cannot be a suitable noble in other respects. The heir is already a noble, just perhaps not a noble suited to running a household. But Ai-Naidar in the noble caste also serve supporting functions to Heads of Household.

Masirked
Primary city family. Nobles charged with an entire city district. Their suggestions have the weight of law.

Nanauked
Major city family

Eritked
Minor city family

Anathked
Primary country family (rules the others)

Rithked
Major country family

Sitriked
Minor country family