The picture below shows a view of the back and buttocks of a male human being.
The back and buttocks are outlined in the picture below.
With the back and buttocks outlined on the right side of the picture, it should be easier to see the penis shape created by the back and buttocks.
To make the penis shape created by the back and buttocks completely clear, the picture is flipped vertically so the penis shape is in the normal orientation for a penis.
The similarity between the head of a real penis and the shape created by the buttocks is highlighted in this picture,
while the similar orientation and shape of a real penis shaft and the back are highlighted in this picture.
