It happens.

Sometimes things go on in the world that are just out of our control. Death, disasters, marriage... But in the end, it all turns out alright. Nothing is umbalanced, good things have to go on to make it all right.
Now, There was this village. It was nice village, full of pokémon and stuff like that. There was a shop, too. Really overpriced, but the owner was nice, at least.
It so happens that in this town one day, a Wynaut arrived. He was smiling cheerily, bouncing around with not a care in the world. Though to be fair, you would expect him to be like that, since every Wynaut's face is permanently frozen like that. In any case, he entered town, a stranger with no past and no reason, simply another pokémon in the crowd. Of course, that was only momentary. He was the protagonist after all, it'd make no sense for him to be just a background character.