Taking notes of some file paths that I can't use here.
https://prd-game-a1-granbluefantasy.akamaized.net/assets_en/img_low/sp/cjs/npc_get_master_story_SIDESTORYID_CHARAID_char.png: Alternative tonpc_get_master_. Used by some characters obtainable in side stories. Require the Side Story ID. It got the alternative_char_wsuffix too.