A gardener could be an important character. He might be an old man who has been taking care of the garden for years and has some wise words for the young woman.
Perhaps a small animal like a squirrel or a bird. They could be her companions in the garden, and their interactions could add charm and a touch of magic to the story, for example, the bird might sing to her every morning.
One possible theme could be nature and its beauty. The garden setting often represents the beauty and tranquility of nature, and the young woman might interact with it in ways that explore this theme, like enjoying the flowers or the peaceful environment.
Since we don't have much context, she could be anyone. She might be an ordinary girl with a passion for the sea, or a character created to represent the relationship between humans and the ocean.
The central character in the 'Promising Young Woman story' is a very determined young woman. Then there are the men that she encounters during her nightly escapades. Some of these men might be seen as antagonists as they are the ones she is trying to expose. There could also be a female friend or acquaintance who might play a role in either supporting or being in contrast to the main character's actions.
Often, there are hunters. Hunters play a significant role as they are the ones who may encounter the deer woman, either by chance or because they are out in the forest looking for deer. Sometimes, there are also local villagers or tribespeople. They might hear stories about the deer woman and be affected by her presence in different ways, like being in awe of her or fearing her.
I'm not sure exactly who the young woman is without reading the story in detail. But she is likely a survivor who has a unique perspective on the Hiroshima bombing.
It could be a young Amazonian who has been chosen by Wonder Woman to be her protege. This character would have the physical and mental strength typical of the Amazons.
Lex Luthor could be a great villain. He's always interested in taking down the Justice League and its affiliates. He might see the clone as a way to disrupt the Young Justice team and gain an advantage over Wonder Woman.
Well, Manny the mammoth could be a main character. He could be like a big brother figure to Roshan, protecting him from the various threats in the Ice Age. Diego the saber - tooth tiger could also be important. Maybe at first he seems menacing but then he warms up to Roshan and becomes his protector too.
It depends on the specific version of the story. But often there are humans, like young warriors or children who interact with the spider woman. Sometimes there are also animal spirits that play important roles in the story, such as the eagle or the coyote.
I don't know exactly who she is without more details about the story. She could be a fictional character created for a horror or mystery story, perhaps a witch or a ghost.