Varyo was born on Lys, as the bastard of Robert Velaryon and Ryaessa Lohar. He was brought up in his mother's house along with Rhaena Ormollen and Lyaan Ormollen, his adopted sisters whom his mother saved from slavery after their family was impoverished. Varyo was trained in traditional court intrigue by his mother and Essosi martial tradition by his stepfather Rhaevo. His mother caught a flux, and fearing for his safety should he be left as head of the now poor house, had Rhaevo steal him away to his father's court with a letter of introduction.
On Driftmark he was grudgingly accepted and eventually at the behest of his brother in law, Lord Bryce Caron, he was even legitimised, although only through meddling by Velaena Waters and Ser Lyn Velaryon. Varyo's father attempted to kill him after his older brother, Daelys Velaryon, announced his intent to join the Kingsguard. Varyo was saved by Rhaevo and Ryman Sunglass, and fled to Essos.
There he regained contact with Lyaan and Rhaena, who had been kept enslaved as courtesans. He and Rhaevo were able to free them, and ladies became the fronts of his properties in Lys. He served in a couple of sellsword companies before Robert Manderly asked him to join the Golden Company as its spymaster.
Rhaevo was killed by Ulrich Dayne shortly after, sending Varyo into a violent spiral. This was made worse when he was robbed of his chance for revenge against his father after the man died in storm.
Varyo seized the Red Keep during the sack of King's Landing in Aerion's name, and in a fit of rage, killed the so-called Blackfyre soon after. Damon Lannister used Varyo many times in the war for political reasons, most infamously in the flaying of Rickon Baratheon. Varyo also burnt large areas of the Reach and Riverlands.
He fled to Lys fearing reprisals from the Lannisters. There he was involved in Anti-Braavosi Riots, and helped to escalate them to the point of a coup. The Magisters elected him to the position of Gonfaloniere, the leader of the city's military. Using his influence, he then declared himself Prince of Lys and violently took control of the city. His daughter Rhaenys Velaryon was born soon after.
With the help of Martyn Dayne, he defeated the forces of Braavos, freeing Volantis and solidifying an alliance with Dorne and its Princess. He later helped strike a deal with Syrio of Myr to create a new alliance. In Lys, he held his nameday celebrations, sent Andrik Harlaw to escort his nephew Aedan on a quest to Tyrosh, and set aside Rhaena whilst taking Mona of the Seahorses as a lover
Varyo heeded the call of Danae, to whom he had promised Lys' aid if she chose to claim the throne in her own right. He discovered that Sarella Martell had exaggerated the matter and the two argued of the need for war. In the end, Varyo was given Danae's blessing to legitimise his older half brother and to place him in Driftmark with the forces he had brought to Dragonstone.
Upon his return to Lys, he was greeted by his brother Daelys who had been instructed by Lyaan to form a knightly order in the face of increased unrest promulgated by Seldys and her Lyseni Chamber. After surviving a supposed assassination attempt, Varyo and Lyaan were able to unwrap the conspiracy against them, and the Prince decided to agree to some of their demands for the greater good; however on his own terms. He would thereafter become a constitutional monarch, with many of his responsibilities handed to an elected Assembly.
Varyo would dispatch the daughter of Moredo Maegyr, a man whom he had grown to trust, to infiltrate the Alchemist's Guild, in order to investigate strange and mystic goings on, rumoured to be occurring. Rymar Royce, fleeing Westeros, came to Lys seeking to sell secrets in return for asylum. However, it would be revealed that Varyo had slept with Sarella at Dragonstone, and that she had revealed that the spymaster had commanded her to murder Varyo and his pregnant wife when he had visited Sunspear. The Prince cut out the spymaster's tongue and beat him to death with a flagon.
After a string of failures in the Assembly, Varyo had his wife removed from power. Influenced by his new Chief Secretary, the Prince instituted a number of reforms, courting the slaver faction of the city. This caused increased unrest with radicals and moderates.
As the tension reached its peak, Varyo was betrayed and a planned coup went into action. Varyo escaped the initial killings, and attempted to rescue his family. His wife and son were killed, but Varyo was able to protect his daughter Rhaenys, and he was killed making sure she escaped.
"Varyo was a slimy and clever creature, a man like himself was destined for power." - Gylen Hightower
"Varyo Velaryon, Prince of Whores, offers you an army of silk wearing bed warmers. Your house's reputation earns you gowns and consorts from the eastern continent." - Damon Lannister to Danae Targaryen
"He could not hate someone who's life had been ruined by Ulrich. He felt a slight sense of guilt rise up at comparing the death of a father to a wife being fucked by a sibling, and struggled to push it down." - Martyn Dayne
"Varyo was a means to an end, nothing more... He postures for position like a young cub hoping to be head of the pride... What is any man after? Power. He has planted a kingdom and now he prepares to water it with blood. His or his enemies though... I doubt even he knows. Lys is only as strong as its gold." - Loren Lannister
"You are a man with ambition. Ambition and the will to power." - Rymar Royce
Daelys Velaryon, brother
Corliss Caron, nephew
Robert Velaryon, father (deceased)
Rhaena Ormollen, former wife (deceased)
Lyaan of Lys, wife (deceased)
Laenor Velaryon, cousin