It can make her relationships strained. Ruby might push her friends away because she's afraid of hurting them or burdening them with her problems. For instance, she could be short - tempered or distant, causing her friends to be confused and concerned.
On the positive side, her PTSD could bring her closer to some characters. If there are others who have also experienced trauma, they might understand her better. They could form a support group of sorts, sharing their experiences and helping each other heal, which in turn strengthens their relationships.
It could strain her relationships. Her friends might be a bit scared or confused by her new form. They may not know how to interact with this 'Red' Ruby at first. For example, Weiss might be more hesitant to trust her, thinking that this change could make Ruby unstable.
On the other hand, it could cause some strain. If Ruby's magic is unpredictable, it might accidentally put her team in danger. This could lead to some arguments and tense moments as they try to figure out how to deal with this new aspect of Ruby. But through communication and training, they would eventually learn to work with her magic and grow even stronger as a team.
Ruby's sleepwalking might also lead to some misunderstandings. If she sleepwalks into Weiss's personal space, Weiss might initially think Ruby is being rude or inconsiderate. But once they figure out it's because of her sleepwalking, it could lead to a deeper understanding between them. Weiss might become more empathetic towards Ruby's involuntary actions, and they could become closer friends.
When Ruby becomes a demon in this fanfiction, her relationships with her team are bound to change drastically. Her new form and the powers that come with it could make her more unpredictable. Her team members like Pyrrha (if she was still around) might see her as a danger to the team. This transformation could lead to a lot of mistrust and conflict within the group as they struggle to come to terms with Ruby's new state.
The betrayal could also make her more empathetic. Ruby might start to understand why people betray others, whether it's due to desperation, greed, or being mislead. This new understanding could make her more forgiving in the long run, but also more determined to prevent future betrayals from happening within her circle of friends and allies.
The Sharingan would give Ruby a significant advantage in battles, allowing her to predict her opponents' moves. But it might also bring complications and challenges, like dealing with the power's drain on her.
If Ruby has a new identity, Weiss might initially be suspicious. Since they have a complex relationship, Weiss could think Ruby is up to something. But as the story unfolds, Weiss might see the good in Ruby's new identity and their bond could strengthen in a different way.
It can create a lot of tension within the team. The story could then focus on how they try to resolve this tension. For example, they might have to have a series of heart - to - heart conversations to understand where Ruby is coming from and vice versa. This can lead to character development for all of them.
On the positive side, if Ruby's dark twin brother were to eventually turn good, it could strengthen Team RWBY. He could bring in new skills and perspectives. For instance, he might have a different combat style that he could teach the others. However, if he remains dark, it could be a constant source of danger for the team. He might try to use Ruby's connection to the team to gain access to information or resources that he could use for his own dark purposes, putting the entire team at risk.
With Weiss, their relationship could be more strained at first. Since Weiss has some preconceived notions about Faunus, she might be initially distrustful of Ruby. But as time goes on, they could overcome this. With Blake, they might bond more deeply as they both share the Faunus experience in a way. And with Yang, Yang would be very protective of Ruby, especially if Ruby faced any discrimination because of being a Faunus.