Headscratchers / Cool Cat Fights Coronavirus

• Just what the hell is Dirty Dog's role supposed to be? Is he meant to be a child like Cool Cat supposedly is? Does he go to school? The narrative treats Cool Cat as if he were a normal human; is Dirty Dog also human-equivalent?
  • Judging from the end in which he threatens to shoot up a school and declares his hatred for school, it's clear that Dirty Dog is supposed to be older than Cool Cat.
• Is Dirty Dog really trying to infect the kids with a disease he doesn't think exists, or is he just trying to scare them? Both have been suggested, but they'd seem to contradict each other.