George's disappearance from the Guesthouse

Axioms

• George did not go down the stairs of the guesthouse.
• All windows and doors leading to the inside were locked from the inside. Furthermore, it is impossible to lock any of those from the outside!

Corollaries

Either Sayo calls out to him and he sneaks out through the window, Nanjo knocks him out and pushes him down, or a combination of the two. Then Nanjo locks the window.