Rosette Christopher/Prier: Both are hot headed sixteen year old girls who will fight for what they believe in at any cost. They are often at odds with others who stick to their religious convictions or direct orders and play by the books. However, their beliefs are still influenced by their religion; both being Sisters and all. Also, they each have a younger brother that they care greatly for; though Joshua is kidnapped by Aion while Culotte is still with the group. And they have a male companion with a black past. Yet, both girls accept not only his past but who he is now, and they fall in love.
Chrono/Croix Raoul: Not as easy to see cuz their demeanors are so different (Chrono being sweet and gentle until Rosette unleashes the seal, and Croix being calm, cool, and collected), but they do exist. Both of them have a dark past; Chrono once fought alongside Aion in his rebellion and Croix was once the Dark Prince. However, they were brought into love and friendship through the trust and love of the female lead. Also, there is a past lover (Magdalene/Angelique) who resembles the female lead and who died right in front of them. This caused the two distress and lead them away from society for awhile (Chrono sealed himself in Magdalen's tomb while Croix loses his humanity and becomes the Dark Prince).
Joshua Cristopher/Culotte: Only a few exist here. Little bro of female lead who feels that he's too weak but must get stronger. Though Culotte didn't accept the horns of a Devil to do so; he fought for what he gained. Also, they are both experts in healing power. Besides, they really didn't need to have Culotte be insane in La Pucelle; Croix's mental problems were enough.
Aion/Noir: Calm cool and collected lead villain. Both wish to create the end of the world in some shape or form. Though they have other Demons supporting their efforts, as well as some humans (Joshua, Fiore, Alan, and Dark Croix do it intentionally, the other Apostles and Barsome are manipulated by events), they could care less if they die. If Aion and Noir are alive, then the plan can continue but if they die it ends.
Magdalene/Angelique: Past love interest of male lead. They both possessed special powers (Magdalene's future vision while Angelique was a healer) and considered holy women who served their deity. A strong resemblance is held towards the female lead (rumors say that Rosette might be Magdalene reincarnated but I'm not sure if that's confirmed in the manga, whereas Prier can't be Angelique's reincarnation unless her essence can exist without her soul seeing as she appears to Prier several times) and their beloved sees her in said female lead on occasions, leading to short flashes that aren't explained at the moment. Her death is unprevented by her lover (though at least Croix didn't have Angie's death on his hands like Chrono has Magdalene's) which causes him to lose his will and hope (locking Chrono in a tomb and Croix's soul within his heart).
In Episode 2 of Chrono Crusade, Rosette is knocked back by a Devil and Chrono berserks; releasing his Devil's powers. He does the same time in Episode 7 when Aion kisses her. It's very similar to what happened in Chapter 9 of La Pucelle when the Demon Lord whose name I can't spell tied Prier up and tried to execute her Angelique style.
In Episode 5, a Demon possesses Azmaria and tries to kill Rosette. In order to save her, Rosette is forced to go into Azmaria's heart and help conquer her inner Demons. It's similar to the fight inside of Croix's heart, though the emotional level is closer to the fight inside of Eclair. And like the Dark Prince, the Mind Eater fed on the negative emotions like despair and loneliness; both only being forced back when the female lead got through to the host.
There is one more subject to note concerning that Demon and things in La Pucelle. First of all, Father Remington states that by taking the bodies of others this creature committed many murders in the Civil War. Similar to how Alan copied the appearances of others to get closer to his victims. Chrono yells something to the extent of, "It's gonna eat their hearts and minds." Every time Alan killed someone, he ripped out their heart; though he only wanted to revive his dead wife with it.
In Episode 11, the Hellhound is trying to kill all the gangsters because a woman's fiance was caught in the crossfire of a police/mafia gun battle and died. She sacrificed her life to call it forth and it fed on her sadness, hatred, and despair. In La Pucelle, Croix became the Dark Prince who wanted to kill off all humans because humans murdered his fiancee and his sadness, hatred, and despair kept his true soul locked inside of his heart until Alouette erased his memory and then Prier entered his heart and Purified it.
In episode 18, Chrono calls Rosette a "light in the dark." While never stated by Croix in the game itself, it also could describe how she heals his heart and allows him to become himself again. I've used the analogy in my fics way before seeing this episode.
Also in this episode, Chrono makes a vow not to let Rosette die, even though it is her fate. This is just like Culotte's vow to protect Alouette. Of course, both vows end up failing.