One key element might be the dogs' emotions of sadness. Another could be the reasons behind their sadness, such as being mistreated or lonely.
One key element could be loss. Maybe Kaguya loses someone she loves dearly, like a close friend or a family member. Another might be isolation. If she's different from those around her, she could be isolated and that would contribute to the sadness of the story.
Well, in the Medusa sad story, the initial situation where she was a normal, beautiful woman is a key element. Then comes the event that led to her curse - Poseidon's actions in Athena's temple and Athena's unjust punishment. Her new form as a Gorgon with the power to turn people to stone made her an outcast. And her final encounter with Perseus, where she was beheaded, is also a very important part of this sad story that reflects the harshness of the Greek mythological world.
The 'sad dog generation story' could be about a group of dogs that are sad perhaps due to abandonment, neglect or difficult living conditions. Maybe it's a story of how they struggle to survive and find love and care in a world that seems to have forgotten them.
I don't have enough details about this story. But it could be that betrayal is a key element. Maybe one of them was betrayed by the other or by other characters in their story.
The setting could be an important element too. If the story is set in a busy city where everything is fast - paced and he has to constantly struggle to keep up because of his eyesight, it can make for a sad story. Imagine him trying to cross the street but being unable to tell when it's safe due to his nearsightedness, and people shouting at him. His internal struggle to fit in and be normal in such an environment is a key part of what could make the 'Mr Magoo Sad Story' sad.
One sad dog story is about a stray dog. It was always wandering alone in the cold streets. People shooed it away most of the time. It had a limp in its leg, perhaps from being hit by a car before. Eventually, it died alone in a corner, with no one to comfort it.
Sure. One sad dog story is about a stray dog that was always looking for food in the garbage. It was so thin and had a broken leg, but no one bothered to help it for a long time until a kind-hearted person finally took it to the vet.
One sad true dog story is about a dog named Max. Max's owner passed away suddenly. Max would wait every day at the front door for his owner to come back. He stopped eating well and became very sad. He just didn't understand why his beloved human was gone.
Sure. There was a dog named Max. He was in the shelter for years because he was a bit old and had some health issues. People always overlooked him. But finally, a kind-hearted woman adopted him. Max was so sad and confused at first in his new home, thinking he might be sent back again. However, with love and care, he gradually became happy.
Once there was a little stray dog. He was so cute with his big brown eyes. He used to wait outside a bakery every day, hoping for some scraps. But people shooed him away most of the time. He looked so sad, his tail between his legs. One day, a kind old lady noticed him and started to feed him regularly. It was a sad start but had a happy ending.