In the movie Your Name the boy Taki and the girl Mitsuha spend a lot of time switching bodies and looking for each other, but have a very hard time doing so.
They are separated in time. This allows for a time loop where Mitsuha who at that point in the story have switched body with Taki many times, go look for him in Tokyo, but Taki does not know her, as to him the story has not happened yet. She gives him her hairband which enables the story to begin for him.
The question is, I understand that they have bonded for the story to be told, but how did it turn out to be exactly those two in the first place. Why Taki? Because she wished to be reborn as a hansome Tokyo boy?