Thousands of years ago, there was a catastrophe in the world, allowing her to witness his emergence.
The last magic he performed in this world was that he would be forgotten by the gods forever.
After that, everything in the world remained the same, except for the story between him and her.
Ten thousand years later, he woke up in the far north and spent thousands of years remembering her.
After waiting for tens of millions of years, only the eternal ice kept him company.
He said that so long had passed that he gradually forgot the face of his old friend and the scene when he first met her.
And the only thing I don't forget is missing.