Another possible main character could be a mentor figure. Someone who has known Jaune for a while and has seen him grow. This person might try to intervene when they notice Jaune's sanity slipping. They could be an older hunter or huntress who has some wisdom to offer, but is also baffled by the power his family seems to have over his mental state.
Perhaps his family has some dark secrets that they try to keep from him. But as he starts to uncover these secrets little by little, the shock and betrayal he feels cause his sanity to slip. For example, if he discovers that his family has been involved in some unethical or immoral activities related to the Grimm or other dangerous elements in the RWBY universe.
Obviously, Jaune would be one of the main characters. And considering the RWBY series, Ruby, Weiss, Blake, and Yang are likely to be involved as well. They are the main protagonists of RWBY and often interact with Jaune. So it's possible that one of them could be the recipient of Jaune's nightly visit.
Ruby would most likely be involved. She's the leader of Team RWBY and has a strong sense of justice. She would be determined to find Jaune no matter what. Weiss could also be involved as she has the resources and skills to help in the search. Her family's influence and her own combat abilities would be useful.
Even some of the antagonists could potentially help Jaune if there is a complex relationship developed in the fanfiction. For example, if an enemy realizes that Jaune's death or continued injury would disrupt some sort of balance, they might step in to heal him, albeit reluctantly.
Obviously, Jaune would be one of the main characters as the title implies he has a baby. The baby itself could also be considered a main character in a sense, as the whole story might revolve around it.
Obviously, Percy would be the central character. His friends like Annabeth, Grover, and other demigods from Camp Half - Blood might also be important. They could be trying to help Percy or might be affected by his insanity. For instance, Annabeth might be desperately searching for a way to bring Percy back to his senses.
Jaune is probably the protagonist around whom the story revolves. As for the Maidens, they are likely characters with special powers. They could be a group of female characters with different personalities and abilities related to elements like fire, water, earth and air. Their interactions with Jaune would be a major part of the story, as they work together or face conflicts within the story's universe.
Iruka would be a likely candidate. He was Naruto's first teacher and has always cared about him. He would probably notice the signs early on and try his best to bring Naruto back from the brink of insanity. He might use his kind words and the bond they share to reach Naruto.
Well, Jaune in RWBY fanfiction can vary a lot. Sometimes he's the underdog who overcomes huge challenges, and other times he might have unique powers or a special backstory.
Jaune is the main character who is taken by Raven. He's the one who will be experiencing all the strange and funny things that Raven puts him through. Raven is the other main character, the one who initiates the whole situation. However, depending on how the fanfiction is written, there could be side characters like Yang who might come looking for Jaune and end up in some humorous encounters with Raven as well.