- "Non, non. S'il vous plaît! Épargne moi; Je t'en supplie!
(No, no. Please! Spare me; I beg you!)"
- ―Portos to his killer moments before the first's death
16th December, 1790
22 July 1752
16 December, 1790
Portos Bourienne, vicomte de Esternay was a transgender Templar operating in Paris during the French Revolution. He was the son of Édmound-Louis Bourienne and Anne Albany, and the older brother of Baptiste Bourienne. He was also the cousin of the American patriot Emily Geiger.
As a member of the Saint Vierge, Portos was a known business-man and art thief, carrying out transactions by selling art he stole from fallen nobles – men and women who had ended their lives as victims of the Frenchmen's "National Razor".
Early life 
Portos was born and raised in the county of Esternay alongside his baby-brother Baptiste. The two had an easy childhood, surrounded by servants and luxury. However, it did not take long before his parents discovered something was strange about Portos. He liked to play in his mother's closet, dressing up in her outfits. Furthermore, when he became older, Portos spent more and more time on buying woman's clothes. At one occasion, he even went to a social gathering dressed as a woman – where he also managed to seduce a man.
However, despite Portos "shame" in the family, he had talents when it came to money. He had an unique mind which his father knew how to exploit. Portos quickly became a bookkeeper of his family – and later the Templar Order. In addition to this, his mother soon found out of his taste of art. From his mother, Portos was tasked to buy arts to a fair price – and selling them for an exorbitant price.
At the age of 20, Portos was recruited into the Templar fold. From a man known as Marcourt, Portos learned how to fight with a sword; from a man known as the King of Beggars, Portos learned how to use a pistol and aim it correctly on his victims.
French Revolution 
Recruitment to the Saint Vierge
During the French Revolution, the Parisian Templar Germain recruited men ad women to his radical branch. Portos and his family decided to join the branch, but after serving them for a short amount of time, they were contacted by Marguerite LaVenduz. The woman told how the Templars and Assassins were equally corrupt and blind by the fear of each other. She knew that the only way to create true peace, the human kind was to follow a number of gods. After she had explained that the humans once had been living in peace under a Civilization that came before. Portos and his family was tempted to join the forces of LaVenduz' offer – creating true peace – so the Bouriennes accepted. Portos' father was a Master Templar of the Order, so he quickly earned respect among the members of the Saint Vierge – and also coming with information from the Inner Sanctum to the organization, involving the whereabouts of weapons and First Civilizations artifacts that belonged to the Templars.
A plot de Kilmister
At some point before the Revolution, Portos' father took interest in a blacksmith named Croix. The blacksmith had later joined the Templar Order and the Saint Vierge. Now, Édmound-Louis – Portos' father – sought after a way he could capture a merchant by using Croix. Short time after, the blacksmith and his soldiers attacked the merchant and his daughters. They brought the man to the Bastille while the daughters was hunted followed by extremists back to their home. During the weeks that followed, Portos would spend his time on spying on the sisters – disguised as both a man and a woman.
After the sisters one day decided to leave the house, Portos decided to – with the help of Kevin de Kilmister – infiltrate the estate. Here, Portos found out that the family had a hold lot of valuables that was worth selling or investigating. Portos ordered Kevin to later return and ransack the building. When Kevin asked why they could not take it right now, Portos answered that if they did something now, the sisters would suspect the Templars were up to something. They needed to strike when they felt safe.
However, Kevin felt this was not right – he therefore ordered Charles Benedetto to attack the building and obtain the valuables the following day. Portos did not knew of this, but he later learned of it when a courier of the Templars told about Benedetto's death. Portos contacted Kevin and demanded an answer, to which he replied that he felt it was right to strike now while they were weak. Portos threw his newspaper at him and asked Kevin to read it. An article that asked for help in bringing down a corrupt crusader was published in the Journal de Paris. Portos lectured Kevin in not acting against him – putting his own interest in front of what was necessary for the cause of the Saint Vierge. Portos then ordered Kevin to return to his estate in Paris, waiting for further orders.
With the death of Jacques Croix and Constance Dufour – the Bouriennes agent – Portos blamed Kevin for the problem: if he had waited, the Assassins would take longer time to find out who was the real threat. Now they were on the tail of the Saint Vierge. Besides, after the Templars' death, Le Marais was slowly turning into the hands of the Assassins. As if that wasn't enough: Constance had guarded the book that had all of the transactions belonging to the Bouriennes. Now it was gone. Without that, the latest transactions executed by the family was nothing but air. Portos then told Kevin to wait until Portos meant it was right to execute a burglary on the estate belonging to the merchant and his family.
Short time after the merchant and his family had left for the market, Kevin was given green light to storm the building. After entering the estate, Kevin was to bring all of the valuables they had marked a few weeks before, and bring it to Portos' and Baptiste's hideouts in Paris – and to his father's storehouse near the Luxembourg Palace. These orders was being dealt with, but so was Kevin de Kilmister.
Portos had been delivered different paintings to his hideout: a building not far form the Church of the Madeleine, and he was not late in selling the paintings and jewelry on the black market. However, a painting of a woman – titled marchioness de Saint-Cyr – he kept for now, until he found the right buyer. The painting had been created by Joseph Duplessis – the same man who had painted the former King of France, Louis XV.
One day however, Portos come back from the market. His servant was carrying a new dress Portos had bought. As he was arriving at his house however, a sergeant told Portos that Assassins had infiltrated the building. Scared for someone to steal his valuables or for them to exposing him in the newspapers, Portos took the sergeant's weapons and ran in to meet the Assassins. Finding one of them in the room where he had placed the painting of Duplessis, Portos told the Assassin to stop what he was doing. He had his sword pointed at the Assassin before he suddenly saw a female Assassin entering through a window – trying to stab him. Portos recognized her as one of the sisters he had targeted, whom he later had learned carried the name Marie-Jeanette Simon. He ordered the two Assassins to stand by the fireplace, and so they did. He demanded to know what their game was. Marie-Jeanette replied that she wanted to retake the painting that belonged to her family. Portos laughed before shooting her. The blow hit Marie-Jeanette in the left arm, and she fell to the ground. The Assassin used his hidden blade and shot Portos in the arm. The man screamed in vain and fled the room. He cried out for support. Soon was the room filled with soldiers. The Assassin fought them off while Marie-Jeanette recovered. After the Assassin had killed them all, the two took the painting and fled through a window.
Portos went underground. He felt it was too risky to be in the house he once lived in. The Assassins knew about it and would hunt him down, whatever the cost. Portos therefore chose to relocate to the La Bièvre. Here, he carried out transactions for the Saint Vierge. He had tried to ask his family for help, but they had turned him down. He had gotten himself into the mess, so he had to get himself out of it again.
While Portos lived in fear in La Bièvre, his brother was suddenly killed while doing some scientific investigations on some blades that had been found in the building of the merchant-family.
16th December 1790, Portos was on his way to Paris' city gated in the south. He had been given a chance to flee the city. The request had come from Marguerite LaVenduz to Master Templar Bourienne. On her orders, Édmound-Louis tasked Portos to bring his – and the Saint Vierge's – money to the city of Troyes where a contact would guard it. When Portos returned, he could live up in the Louvre-district – in a house bought by his father. What Portos did not knew, was that Marguerite's precise orders was: Let your son carry out one last order for us, and when he returns to Paris, kill him – he is to no use for us any longer.
Arriving at the city-gates in a carriage with a cart loaded with the goods, Portos was soon let through the gates – dressed as a noblewoman. The guards tried to flirt with him, but backed when they heard his male voice. This let him go through the gates faster.
However, Portos had only left the city of Paris and crossed a little bridge when the escort was suddenly attacked. A smoke bomb blinded the escort, and Portos left the carriage – trying to get back into the city. It was difficult to run in high heels however. He stopped and took them off before running further. This little stop, however, was enough for one of the attackers to aim and fire at Portos. The Templar was shot in the foot and fell to the ground. Screaming over being covered in dirt, Portos began to crawl back to the city gates. When the Assassin approached Portos, the man pulled out his pistol to fire, but the Assassin kicked it out of his hand. Portos began to beg for his life, praying her to let him live. The Assassin seemed not care for the begging. She found her spear and impaled Portos through the stomach, leaving him to bleed to death.
- Portos is a reference to one of Alexandre Dumas' three musketeers: Porthos.
- Bourienne is the name of one of Leo Tolstoy's characters: mademoiselle Bourienne – princess Marya Bolkonskaya's companion
- Portos is portrayed by the Chevalier d'Éon, whom also was a transgender