Glossary
Character Reference
Short answer
A reference method that keeps the same character consistent across different scenes.
A character reference carries a person's face and overall appearance into new generations. It is mandatory for children's books, comics and brand mascots.
In Midjourney it is given with `--cref`; the `--cw` value sets how tightly the likeness binds (a high value also fixes the clothing, a low one only the face).
If you need complete consistency, the stronger method is training a LoRA for the character, which is done on the Stable Diffusion side.