Cosette D'Artagnan/Relationships

Athos
Like the original, Cosette thought Athos killed her father and rendered her an orphan and attacked him without hesitation. However, after saving hi slife, Athos appears to have warmed up to Cosette by the end fo the episode, joining her card game with Porthos to prevent Porthos from conning who he calls "[their] new recruit." During the third episode, Cosette's and Athos' relationship has improved, as they now consider each other friends. However, Cosette finds it irritating that Athos doesn't open up to her like he does with Aramis and Porthos. However, he finally decides to finally open up to Cosette what happened to his wife, something he never shared even with Aramis and Porthos. She promises to him that she won't tell them what happened between them.

Aramis
Cosette and Aramis didn't have a healthy relationship with each other at first, as they dueled against each other since Cosette nearly killed Athos. He often has to hold Cosette back when she goes too far, such as putting a hand on her shoulder to both stop attacking the guard they were trying to interrogate and comfort her at the same time. He often gives Cosette tips about relationships.

Aramis learns she is a girl in episode ten when going to patch her up after being wounded by Athos, but immediately forgave her.

Porthos
Despite not interacting much with Porthos, he and Cosette have a close companionship. Cosette had the upmost sympathy for Porthos when he talked of slavery and revealed personal things about his mother. She excessively worried about him during "The Homecoming," especially instead of saying she was as worried as that, instead Cosette said that to Aramis in order to probably control her worry.

Constance Bonacieux
Constance is an older sisterly figure towards Cosette. At first, the two of them do not get along and Constance think it is foolish that Cosette is pretending to be aboy to kill Athos. However, they begin a friendship after the ordeal is over. Cosette even allows Constance to call her "Cos," a nickname all her friends use. Constance even keeps her secret from Athos, Aramis and Porthos and helps Cosette sometimes embrace her feminine side.

However, their relationship is strained when Bonacieux, Constance's husband threatens to reveal Cosette's secret to the Cardinal if she doesn't break her friendship off with Cosette. Of course, Cosette is unaware of this and is actually heart-broken when Constance breaks the friendship with her.

Milady de Winter
Cosette first encountered Milady when staying at an inn at Paris. However, she came in on a terrible time, since Milady framed Cosette for murder. Milady  first introduced herself as "Anne," and said that as women, they should stick together. Cosette didn't know her as Milady de Winter yet, shown when she denied knowing anyone named "De Winter."

According to Cosette, Milady is very beautiful and says that they have unfinished business.

Her sisters
Cosette loves her sisters dearly and cannot bring herself to tell them of their father's deaths until she has avenged him. Though they disapprove of her masquarade as a boy, they nonetheless support her.

Jacques and Adam Beauchamp
Jacques and Adam Beauchamp are a pair of brothers, Isabelle and Amelia's husbands and  Cosette's brothers-in-law. The two men treat Cosette as the little sister they never had since they only have a younger sister. They defended her against Porthos when they thought he was beating her. They know of her secret and worry about Cosette but learn she can fight quite well when fighting off bandits.

Sapphire
Sapphire is Cosette's pet horse and, after the farm is burnt down, the only connection she has to her mother. She was a gift to Cosette from her mother, Renée, and uses her when travelling to find Athos' innocence. The two fo them trust each other completely, and Sapphire loves it when Cosette feeds her carrots.

She also is the fastest horse in France, even cornering Emile Bonnaire when he attempted to escape, showing a good faith Cosette has in her horse.