With his Pokemon, the bond could become even deeper. Since Calem is immortal, he has an infinite amount of time to train and bond with them. However, his Pokemon might also sense his immortality as something different and it could affect their relationship in unexpected ways. For instance, some Pokemon might be more protective of him because they know he can't die in the normal way.
His relationships with his friends would likely become strained. They would age while he stays the same. For example, his best friend might start to feel a sense of envy or resentment as Calem doesn't have to face the normal passage of time. His family might be confused and worried about his immortality at first.
One possibility could be that Calem's immortality is a result of some ancient Pokemon power. Maybe he stumbles upon a hidden temple in the Kalos region where a powerful Pokemon bestows this gift upon him. This would lead to him having to deal with the loneliness that comes with immortality as he watches his friends and family age and pass away.
One great fanfiction is 'A Journey with Serena and Calem'. It focuses on their adventures in the Kalos region, exploring how their relationship develops during battles and while facing various challenges. The author does a wonderful job of capturing their personalities as seen in the game.
I think Professor Sycamore would be an interesting character to pair with Calem in fanfiction. Calem could be his assistant for a special research project on Mega Evolution. This would give Calem a chance to learn more about the secrets of Pokemon from the professor. Also, Tierno could be paired with Calem. They could have a dance - off with their Pokemon, which would be a really fun and unique scenario in the fanfiction.
One idea could be Calem's journey after becoming the champion. Maybe he travels to other regions to learn new battle strategies and meet different Pokemon. Another could be a story where Calem has to team up with his old rivals to face a new, powerful threat to the Kalos region.
The plot also matters a great deal. It could be something related to their Pokemon journey, like exploring new areas in Kalos that weren't fully covered in the game. Or it could be a more personal story, like Serena dealing with homesickness and Calem helping her through it. A good balance between action - packed Pokemon battles and emotional character moments is key. In a story I read, they were on a quest to find a legendary Pokemon, and along the way, they had heart - to - heart conversations that deepened their relationship.
With her rivals, it could become more complex. They might initially see her pregnancy as a weakness, but as time goes on, they could grow to respect her more for handling it bravely. For example, a rival who was once very competitive might start to offer her help or advice.
The characters Calem and Serena themselves are very interesting. Their relationship in the game can be explored further in fanfiction, like their adventures together that might not be fully shown in the game. It gives fans a chance to see more of their dynamic.
You can start by looking on fanfiction websites like FanFiction.net or Archive of Our Own. They have a large collection of Pokemon X and Y fanfictions featuring Calem and Serena. Just use the search function and type in the relevant keywords.
Ash's relationships with his Pokemon would likely change significantly. Kalos has its own unique ecosystem and Pokemon culture. His Pokemon would be exposed to new stimuli and experiences. For instance, the Kalosian food for Pokemon might be different, and Ash would need to figure out how his Pokemon like it. Also, new training methods in Kalos could either strengthen or test the relationships. Ash would need to be more attuned to his Pokemon's needs and feelings in this new environment.
If Naruto were not human, his relationships would likely be very different. For example, his relationship with Sasuke might be more strained. Sasuke, who is very focused on power and revenge, might see Naruto as a greater threat if he's not human. He could view Naruto's non - human abilities as something to envy or fear. With Sakura, she might be more hesitant around Naruto. Instead of her initial crush, she could be more cautious, not knowing what Naruto is truly capable of.