The character that I write in stories looks the exact same in each one because she's an OC. She's usually around the same age in each story as well. I change her name and slightly change her personality because I want her to be slightly different in each story. It's fun coming up with different names for her and slightly altering her personality.
In the newest story I'm currently writing, she will have a different age. She's usually really young but in this one she'll be an adult. Although, she will be a little/age regressor. Just thought I'd explain to why she always has the same looks