It represents a diagonal lines photograph example. This was in a father, a son, a disease and a camera story. We can see those lines in those lockers, even the walls. there are horizontal and vertical lines. the line of the window matches the line of the wall and all the locker doors are in a diagonal lines as shown.
This photo we took me and Ari in class, it represents Diagonals.
I know your category was diagonals but it could have been a frame within a frame. the man in the locker room is nicely framed by the walls, making him feel a bit trapped. In the shot, you took it is the strength of the negative shape of the sky that stands out.