Serenei's exact appearance is unknown, but she was considered by many to have been the most beautiful of Aegon's many mistresses.
Serenei was the last daughter of an ancient and impoverished Valyrian noble family, born in Lys. She was cold and haughty towards the members of Aegon's court. It was rumoured that she was much older than she looked, older than the king even, and that she practiced dark arts to maintain her youth and beauty. These rumours would also follow her daughter. Serenei died in childbirth.