The dataR.cpk file found in Persona 5 Royal contains a GMD model folder, Model (P5R). Each folder is categorized by character ID number. See Model (P5R) for a full list of ID number with character names and descriptions. 4267 refers to P5R's Mika, and contains 2 GMD models related to her.
|0||c4267_000_00.GMD||Model||Outfit worn when modelling|
|71||c4267_071_00.GMD||Model 2||Another outfit worn when modelling|