|Name in Japanese||マクシミリアン・ロベスピエール|
|Voice Actor (Japanese)||Takahiro Sakurai|
|Voice Actor (English)||Amit Patel|
|Relatives|| King Louis XIV (father)|
Lia de Beaumont (paternal half-sister)
D'Eon de Beaumont (paternal half-brother)
|Affiliation/s||NQM ( previous ), Revolutionary Brethren ( previous? )|
Maximilien Robespierre (マクシミリアン・ロベスピエール Makushimirian・Robesupieeru )is a blond Poet with personal relations to Durand and Lia de Beaumont. He is first seen leaving France with the Russian spy Vorontsov. Formerly a French secret agent, he turned against the King shortly before Lia's death.
In the anime he frequently asks Durand to join his Revolutionary Order and haunts D'Eon for being the vessel of Lia. D'eon doesn't know why he was doing this until he found out Maximilien and Lia were lovers and that he, Lia, and Maximilien are half siblings from their father having an affair with another woman, and that the royal family is the reason Lia is dead.
He and Lia were once lovers, until they both found out to be half-siblings both sharing the same father. The truth devastated both of them and soon started to drift apart.
He is usually calm and emotionless, wielding the Psalms almost apathetically but powerfully. But did show to be mournful when Lia died as he placed her in the coffin with a flower with her before pushing her coffin to Paris, hinting he still loved her even though they were half siblings. He's also shown great anger when Lia told him they were half siblings by having the same father, devastating them both that they could never be together as their union would be incest and he hated and blamed his father for his infidelity when he fathered him and his half siblings with other women that led him and Lia making the mistake of being lovers and when they learnt the horrible truth that destroyed them and their relationship.
Lia's death convinced Maximilien that the royal family causes nothing but chaos and misery to the people and it costed Lia her life and happiness. Since then he dedicated his life fighting against the crown for being tossed away at birth by his real father the king and how Lia was hurt because of their father's actions and why she and Maximillien can never be together and was killed for working for the royal family she was loyal to and who failed to save her.
While he could not convince Durand or D'Eon into turning against the King, eventually Robin follows his ideals and even takes his name. He is the true member of the royal family.