A failure? How could this possibly be a failure?
Your characters are well drawn and have been given good poses; as well you have consistent lighting for both of them in regards to the street lamp above.
The only thing missing would be the top of the window ledges, as the perspective as it stands would show a small amount of the concrete it is fastened to if you are looking up at it.
If you learned something, then a piece of art can't be a failure. :)
Don't give up!