How does the main reference photo interact with additional character references?

What are you trying to do?
Trying to understand if the main reference photo should be the main singer. A full body view of the character front facing?
Then in the additional character ref's, is that were you add closeup views of the face, etc? Then for the additional character ref's description, do we just put a tag like "singer" in it?

the speaker_00 should also have the same tag "singer" and role of "singing"?