Rules can be broken. Artists, including photographers, know that light objects draw the most attention in a scene. Careful composition makes sure that subjects are either the lightest item in a scene or they are placed inside the lightest area to insure the viewer clearly knows who/what is most important. These two images break that rule; both images have the subject very dark with lighter areas away from the subject.
The effect of placing the subject outside the brightest area forces the viewer to look at the entire image. Eyes will wander through the image and finally rest on the dark subject. These both are complicated scenes, with multiple interest areas to be viewed and enjoyed. Despite these complicated scenes, the primary subject in each image is clearly evident.