Georges Seurat,Bathing at Asnieres, 1884
Georges Seurat is notorious for his use of the "weird dog in the corner". This is quintessential "weird dog in the corner.
As composition gets more complex it is not only about the placement of objects but also the relationships or connections of those objects. The weird dog brings the eye back to the visual center with his line of sight. If you focus on the dog-shaped things (thanks paul) you can pick out the connections to the weird dog in the corner. Look at the dog head compared to the shape of the dark boot and directly below the white towel. Also notice the dog body shape. It repeats all of the hat-things. The black dot of the dog's nose connects to the black dot in the man's ear. There is also a sense of tension created where the dog's body curves out opposite of where the man's body curves in. The dog's nose curves in where the man's shoulder curves out. These echoing and opposite tensions serve as a means to connect the elements diagonally. Seraut is also connecting foreground and background with "dog colored" things and "dog colored" dots.