>>53147573Protag Gamerena is mostly a blank slate, the only reliable reference for personality is her Masters appearance.
Rival serena is wants to help the protagonist become a better version of herself, she realizes there's no one else who can help Calem like her as there's no other trainer that has gone through so much along him. She's also probably the second strongest trainer in Kalos, as it has been the case with all rivals since Cheren (ORAS May being the only exception for obvious reasons).
Y was being forced by Grace to train as a Rhyhorn racer so she could become her succesor. A young X made her realize she should do what she wanted do instead. X was cheery and she was all deppresive. Skip a few years and now X is the deppresive one while Y took on the optimistic, level headed friend role instead. Think of both Jinta and Anaru from AnoHana, something akin to that, except the story is a typical shounen that tushes a lot of the plot and its only redeeming quality is how fleshed out are the main characters in cimparisonto their game counterparts, Shauna, Tierno and Trevor being the most notable example.
