Characters can be anything you want - even a toaster has been a character in a book and movie!
fiction stories
Most stories have both male and female characters.
Yes, they're called literary stories - stories just to show different writing techniques.
invented
Why would anyone want to read about boring characters?
the narrator of the story are the dogs because they mention the dogs a lot
The same sorts of characters that there are in any story! Gothic stories are spooky romance tales, so anyone can be involved in one.
memorable characters
mythological characters and stories
Yes
The Evolution of Trickster Stories Among the Dogs of North Park After the Change was created in 2007.
It means that show writers welcome suggestion of characters for their stories.