His relationship with his uncle Iroh would be deeply affected. Iroh has always been a guiding figure for Zuko. If Zuko turns into a dragon, Iroh would be worried but also proud in a way. He would search for ways to help Zuko, and their relationship would become more about Iroh protecting and guiding Zuko in this new and strange form. Zuko, in turn, would rely more on his uncle's wisdom during this time.
In a fanfiction where Issei turns into a dragon, his relationships would be in flux. His relationship with his mentors or those he looks up to might change as they now see him as a different kind of being. They might treat him with more caution or more respect depending on how they view dragons. His friendships with his peers would also be altered. Some might see him as a weapon to be used in their battles or struggles, while others would see him as a friend in need of support. Romantically, if he had feelings for someone, that person would have to deal with the fact that Issei is no longer fully human. There could be jealousy from others who might want to be with the powerful dragon - Issei, or there could be newfound admiration from those who previously overlooked him.
His friends would be both amazed and a bit scared at first. Hermione would immediately start researching ways to turn him back. Ron might be more in awe of Harry's new form, but also worried about how dangerous it could be. Their dynamic would shift as they now have to protect Harry in a different way. They might also have to hide his transformation from others who could misunderstand and try to harm Harry.
With his human friends, it would be really tough. They might be scared of him at first. Astrid, for example, would be conflicted. She was attracted to Hiccup as a human, but now he's a dragon. She would have to overcome her fear and try to find a way to communicate with him. And Hiccup would feel isolated from his human friends, longing for the connection they once had.
His friends would probably be initially shocked. Hermione might be a bit scared at first but then would be very interested in studying his new form. Ron would likely be in awe but also a bit jealous of Harry's new power as a dragon. Overall, their friendship would have a new dynamic as they have to adapt to Harry's different form.
His relationship with Sasuke could become more complex. Sasuke might be both envious of Naruto's new power and also worried about Naruto losing his humanity in the dragon form. Sakura could be initially scared but then determined to help Naruto control his form, which would strengthen their friendship. His relationship with Kakashi would change as Kakashi would now have to mentor Naruto in a different way, guiding him to use his dragon powers for good and not let them consume him.
If a character turns into a dragon, their relationships would change drastically. For example, if it was a knight who had many friends among the other knights, they would be seen as a threat once they start to transform. Their former friends might try to hunt them down out of fear. On the other hand, if it was a character who was previously an outcast, like a bastard, their new form could give them power and respect. They could form new alliances with those who seek to use a dragon's power for their own gain.
Inuyasha's relationship with his enemies would also change. Some enemies might underestimate him in his baby form, not seeing him as a threat. However, some might see it as an opportunity to get rid of him once and for all. His friends would have to be extra vigilant in protecting him. And as Inuyasha grows up again in the story, his relationships with his friends would be different because of this experience. They would have a shared memory of taking care of him when he was at his most vulnerable, which could deepen their loyalty and friendship.
His relationship with Kagome would change significantly. Kagome might see Inuyasha in a new light, perhaps more as a sister - like figure at first, but then as she gets used to the new form, there could be a shift in their romantic undertones. With Miroku, Miroku would be more respectful in a different way. He might be less likely to tease Inuyasha in the same way he did before. Sesshomaru, on the other hand, might initially be disgusted or confused by his half - brother's new form, but it could also lead to some interesting developments in their rivalry as Sesshomaru tries to figure out if this new Inuyasha is still a worthy opponent.
His relationship with MJ would be severely strained. She would be terrified of this new, violent - looking Peter. She might try to distance herself at first, but then later try to bring back the old Peter.
Well, his relationship with Sasuke could be very interesting. Sasuke might see Naruto's fox form as a new level of power to either compete with or respect. Naruto, on the other hand, might be more protective of his friends in his fox form, which could make Sasuke question his own motives. And for his other friends like Shikamaru, he would have to come up with new strategies to work with Naruto in this new form.