Sounds like a quickly moving man wearing dark clothing to me. Cloaks aren't common outer wear where I live these days, but they aren't unheard of. After he stepped behind your neighbor's car he changed direction and turned to walk straight away from you, and so did't reappear on the other side of the car. You only saw him for a moment, and so didn't have the chance for a better look. I'm not having too much trouble imagining how this might happen. Why do you think it's a paranormal event? . .
It's probably an artifact of something else - shadows, tree branches, etc. It's your pattern seeking brain that makes the connection to human shapes, cloaks etc. Did you go and investigate?
Sounds freaky! Reminds me of the Ghost Hunter's episode when they saw a cloaked figure at a penitentiary. I'd be thinking it was a grim reaper too. Be careful driving and in anything you do. It could be a bad omen?