The Culture

The ruling class of the Zivot Empire, called High Elves, practiced Endogamy in their culture. 

They preserved their bloodlines and did not allow the males and females of their families and clans to marry anyone outside or below their social standing; not even with the normal elves of the empire. 

Premarital sex and post-marital affairs for the High Elves were taboo as per the laws. 

The punishment for these 3 crimes was straight-up execution of the culprit and the person they married to or had an affair with. 

But this was also the most effective and viable practice that maintained their bloodline purity and elite standing in the empire above everyone else. 

After the High Elves, the highest standing regardless of their origins were the normal Elves.