Characters created by changing colors, clothes and parts of an existing character are called "models".
For example, you can add the model data of a girl with black, long hair and, based on it, model data of the same black haired girl in a uniform, with cat ears, or of the same girl but with silver long hair instead. If multiple models are registered under the same character, they can all be displayed on the character's page.
Since the VRM file of each model is independent, usage conditions can be set separately for each model.