The letter scene made me cried again, we knew we would cried but we build emotions anyway and we brake.
And yes, I'm still confused about the DVD shop's owner. A spirit keeping all its own memories in all the possible timeline existing in the entire reality ?
I like simply keeping it poetic with the blue butterfly as a keeper of memories, the butterfly store the mutual memories of Ongsa and Swansoon, a bit like a proxy, or I don't know the technical term for it (I am notoriuously bad in informatic)... is it Cloud Network ?
So, in the butterfly, the shared memories, the scenes that were not supposed to happens did happened in their own reality.
Complicated but made sense to me.