I really like this photo for several reasons:

-bright, contrasting colors

-lots of lines (on concrete, on tie, in water, way the body is bent) and the lines are really simple giving the photo a very geometric look.

-the strong shadows both in the water and on the body.

-the relaxed "chilling by the pool" pose. it makes it look a little more natural and less like a fashion ad.

and it makes me really wish i had a pool to take pictures by