Lehen had explored Valhalla long before the days of Trinity Cluster. She was truly exploring Valhalla. She came from the outside world to explore all of Valhalla. It is conveyed that she lived her life pursuing her inquiring mind as if she never aged.
Yokoshima was born in Valhalla.
He can create various things. He enjoys creating and continues to create.
Even if his work is scrapped, it can be restored in his hands. Once he has made something, he does not care if it is in a cemetery.