I love to play around in Photoshop. Living in New York City doesn't really allow me to take Sasha out and photograph on "location" so I create location photos in Photoshop.
Gregor in Central Park is made from two photos. The trick to making a created photo look real is in the lighting. Make sure both images have the same light source. If you look closely you can see the light is hitting the buildings and Gregor from the same side.
Sasha in the Garden is really three images. The background is one photo, the foreground is another, and Sasha is "sandwiched" between them.
It takes a lot of time to make really good photo montages that appear real. These are just what I call "quickies" and not really as good as they could be if I wanted to spend more time.
And they are fun to do.