|Agnès Chevalier de Milan|
|Country||Village of D’Angleterre, Tristain|
|Occupation||Captain of Tristain's Royal Musketeers|
|Master||Henrietta de Tristain|
|Skills||Master swordsman, expert sharpshooter|
|Dislikes||Mages, being deceived, especially the fire mages|
|Voiced by||Michiko Neya|
When she was a child, her village, D'Angleterre, was burned down by fire mages due to rumors that it was infested with a plague. While she did survive thanks to one of the mages, she has grown to despise most magic users and is openly suspicious, and antagonistic toward them. A calm and level-headed warrior, her talents have allowed her to rise up and become both Henrietta's bodyguard and confidante. In spite of her serious nature she has allowed herself to open up around a handful of individuals such as the aforementioned Queen and Saito. According to Siesta, it is rumored that she is lesbian though their no evidence of this.
She works at the Tristain Academy of Magic to teach the students how to fight. She trained Saito to wield a wooden sword, due to the fact he is unable to access Gandálfr’s power when using it, since it is not a weapon meant for battle. This later came in handy when Saito had to fight Michelle, but couldn't use a real weapon. When Lishimon is suspected of treason, it is up for Her Majesty, Henrietta, to decide go under cover and find out whether or not he is guilty. Agnès goes on this mission with the princess at her request, and also for a chance at vengeance. When Lishimon is found guilty, he escapes from a trap door in the theater. When he is about to escape, Agnès appears, pointing a gun at him. He tricks her into lowering her guard, by informing her that the D’Angleterre records are in the basement of the academy, and uses that chance to blast fire at her. Just when he thinks that she’s dead, Agnès had carried a bag of water that absorbed most of the fire magic if used. She charges out of the flames and stabs Lishimon, killing him and getting her revenge.
Later, Agnès heads to the underground library Lishimon spoke of. On the way Colbert, who was one of the people tagging along with her, asked her if she's ever fallen in love. Agnès replies that she has no time for such things. Colbert then questions why she plans on wasting her life on war and revenge. When they arrive in the library, it is revealed that a Special Task Force was formed to fight rebel forces, but they couldn't find anything, and so the plan was changed. Instead they would burn the village of D’Angleterre in order to prevent the spread of plague. Before she can find out the name of the Captain of the Task Force, the library started to attack everybody because of a magic trap if any magic was used in the library. She gets injured on the way out, and Colbert makes her get on his back. As he runs for safety, she pictures herself as a child, being carried on the back of a stranger, who had rescued her from the burning village. They were able to get across the bridge before it collapses. One night the Magic Academy is attacked, and hostages are taken. Agnès gathers her troops to save them. She then battles with the man in charge of the attack, and soon believes that he was the Captain of the Special Task Force, though he informs her that she is wrong, and that he was the Vice Captain. He then informs her that the true Captain was Flame Snake. He had tried betraying the Captain, by blasting him with fire from behind, but the Captain had blasted his attack back in his direction, scarring the Vice Captain's face.
Colbert, Tabitha, Louise, Saito, and Kirche then come to rescue the hostages (in the novel, Louise and Saito do not come). The former Vice Captain soon realizes that he knows who Colbert was, and refers to him as 'Captain': Colbert had been Flame Snake. Colbert and the man then begin to fight, while the hostages escape, the only one remaining is Agnès. She thinks to herself how it was Colbert who took everything away from her, and she then charges at him, ready to kill.
When she tries to interfere, the man shoots fire at her, and when one comes close, Colbert pushes her out of the way, getting hit by the blast in her stead. Part of his robe gets burned off, revealing a scar on his back. Agnès then recalls the night the stranger had saved her after D’Angleterre was burned down, the stranger had a bad wound on his back: Colbert had been the stranger.
When the attacker prepares to send the finishing blow to Colbert, Agnès charges at him, saying she is going to get revenge for her village, and then stabs him, killing him. She then walks towards the injured Colbert, who asks if she is alright. When he sees that she is he is glad, and then collapses. She asks him why he saved her from the fire in D’Angleterre, and he told her it was because he realized he had made a mistake. Colbert claims that Agnès has the right to kill him. Colbert then falls unconscious, and Agnès is prepared to kill him. To save him Tabitha puts a spell on Colbert, that makes him appear dead. In the light novel, Kirche tricks Agnès into thinking he's dead. Agnès later finds Saito and Louise, and hands them a letter she had found with Colbert's belongings. Louise reads it; it says that Colbert had planned on giving him this when he went to a battlefield. It also said that Colbert had made a mortal sin which he dearly regretted, and that he knew he could never make up for it. He wanted Saito to make sure he didn't make killing or fighting a habit, and that he wished to one day to go to Saito's world with him. Agnès says that what Colbert wrote was selfish, and Louise asks Agnès if she will ever forgive him. Agnès replies that she doesn't know, and walks away.
Angès is seen several times after this. She seems to have developed a friendship with Saito. When Agnès learns that Saito no longer has Gandálfr's powers, she trains with him to fight. She does this because she is aware that Saito wants to protect Louise.
When Colbert and the others head towards Germania to act as a decoy for Saito and the others to enter Gallia, they eventually surrender. Agnès comes to them, and is mortified when she sees Colbert is alive. She runs towards him, ready to kill, but she doesn't, since she has to get him to Henrietta, first.
When Colbert is set released from prison, Agnès brings him to his students and Siesta. She tells him she will never forgive him for what he did to her village, even though he saved her life. She says she will always want to kill him, but she can't. If she kills him out of anger, his students will hate her. The chain of hatred will continue, but she is given an opportunity to end that chain. Angès chooses to end the chain. She even gives Colbert assistants from the Firearm Squadron to rescue Tabitha.