Voynich Shift - Planet Killer

Parker Raymond is a completely normal man, but with one difference. He can travel through space time and reach other dimensions... The only problem is, he wanders aimlessly with the device that allows him to travel, unable to determine what will happen on each of the many worlds he travels to.
This time, he lands in a large city that lacks human civilization. What is different about this dimension? What is the reason for Parker's loneliness in this world?

Thank you to @CAMalosh for making my cover art! It looks really great!