Serenei of Lys
From A Wiki of Ice and Fire
|Book(s)||The World of Ice and Fire (mentioned)|
Serenei was considered by many to be the most lovely of Aegon's mistresses.
Lady Serenei was the last daughter from an ancient but impoverished Valyrian noble family. She was cold and haughty towards others at court. Rumors spread that that she was much older than the king, practicing dark arts to retain her youth and beauty.