He might also interact with characters that are no longer alive in his present time. For example, an older werewolf or a witch who was powerful in the past. These interactions could provide Stiles with valuable knowledge or magic that he can use to his advantage when he returns to his own time. It could also create some really cool action scenes and moments of discovery as he uncovers secrets long forgotten.
Another character he could interact with is Thor. Thor's otherworldly nature and his powerful abilities would be quite a contrast to Stiles. Maybe Stiles could help Thor understand some earthly concepts while Thor could teach Stiles about Asgardian culture and power.
Edward is a popular character to pair with Stiles. Their personalities are quite different, with Edward's brooding nature and Stiles' more energetic and sarcastic self, which makes for an interesting dynamic. Another popular pairing is Stiles and Jacob. They could bond over their experiences with the supernatural and their protectiveness towards their friends and loved ones.
One interesting plot could be Stiles going back in time and trying to prevent a major tragedy from happening in the past that has consequences in his present. For example, he might stop a villain from getting a powerful artifact that later causes chaos in his own time.
Obviously, Goku would be a main character he'd interact with. If he goes back to when Goku was a kid, he could train with him, or try to convince Goku's grandpa to let him train Goku in a different way. Another character would be Bulma. If he goes back far enough, he could meet a younger Bulma and perhaps change their relationship dynamics. He might also interact with his younger self. This could lead to some really interesting self - reflection and growth as he tries to guide his younger, more hot - headed self.
Obviously, he would interact with his younger self. He could try to guide his younger self, offer advice on how to control the Force better and how to deal with the temptations of the Dark Side.
Bilbo would likely interact with Gandalf again. Since Gandalf has a long presence in Middle - earth's history, he could be a key figure for Bilbo in the past. Also, the dwarves, especially Thorin Oakenshield. If Bilbo goes back to a time related to the Lonely Mountain, he would surely cross paths with them. And elves like Elrond. Elrond has a vast knowledge and his presence in different historical events makes him a likely character for Bilbo to meet.
His father could be one of the supporters. His father has always been there for Stiles, and he would understand if Stiles was standing up for what's right within the pack. Another possibility is Lydia. She's a smart and powerful character herself, and she might see the value in Stiles' actions and support him.
Peter might be initially suspicious. He's not always the most trusting character. He could wonder what Stiles really wants or if there's some kind of ulterior motive behind Stiles' request for help.
One of the most common characters is definitely her father, Ned Stark. Since Sansa has the chance to go back in time, she would likely interact with him a great deal to try and change the course of events. Another is Arya. They could team up and use their combined knowledge and skills to make a difference. And of course, Littlefinger. Sansa would be more aware of his manipulations this time around and might interact with him in a more strategic way to outwit him.
Well, obviously she'll interact with her past self. It would be really interesting to see how she reacts to seeing a younger and more naive version of herself. She could also meet characters who are no longer alive in the present. For example, if there were any great wizards from the past who played important roles in the history of magic. Additionally, she might cross paths with some of the villains from the past who were causing trouble long before the current villains in the story. This could change her perspective on the whole conflict in the present.