Maekar Lux was a young man serving as a powerful Swordspell and a Priest of R'hllor who becomes a loyal advisor to Aegon VI Targaryen as he attempts to make claim his rightful place upon the Iron Throne, Maekar is the age of the Targaryen Prince and seems to believe that his Priestess Sister-in-arms Melisandre was wrong about Stannis Baratheon as he has found the reincarnation of Azor Ahai to himself, and that Melisandre who helped to raise him has kept a secret from him his entire life.
In a Fire Message between Melisandre and Maekar, Melisandre spitefully reveals that Maekar was the outcome of a spell upon a pregnant woman to summon the Lord of Light into a human body, an argument that Maekar's outlash seemed to cause the flames near Melisandre to strike out against her. Maekar is currently confirmed to be the Host of R'hllor and thus is the Lord of Light in all his power but instead limited by human form, and that the last time R'hllor descended from among his fellow Gods to be born as a mortal, was when he stood beside the only man he ever came to love - Azor Ahai - to rout the White Walkers and the Great Other during the last Long Night.
- Maekar is a High Valyrian name, it is closely related to the english word "Maker".
- Lux is a Latin word meaning "Light".