Jason Aaron 
Once Upon a Time at the End of the World #2 [PDF ebook] 

Jason Aaron and Alexandre Tefenkgi’s fable of a bleak future continues in Maceo and Mezzy’s childhood years, with nothing but Mezzy’s guidebook and her skills as a wastelander to get them through their dangerous, post-apocalyptic journey. As time passes and they endure the horrors of plastic tornadoes and frozen sludge, Maceo proves to be more than just a burden, and they make a connection where none seemed possible at first. But to their unexpected peril, they might not be as alone as they thought