Special Notebook

It's an unnamed object from Oda's God's Gift for the Future oneshot.

God himself is the owner of this notebook, though he lent it to Bran for one day.

The special effects of the "artifact" will only appear if you write with the Pen of Fate. Anything you write with it will happen, just like an agenda of the future. If you want to cancel the effects, you must use the Eraser of Fate. If you erase it with just any eraser, it will happen anyway.