If you listen to the title songthere will be severe charactersThey are all unlockables

CLAUDE-Okayif you don't get this guy you are an idoitSame for Rena too
DIAS-Only unlockable in Rena's storybut I played through Claude's so sorry
CELINE-Claude will offer her to join them after discover the ANCIENT TEXT in the KROSSE CAVESelect the top oneHighly recommanded cause she is a perfect symboligist
ASHTON-He is the guy with two dragons on his backHe carries two bladesbut if you unlock himyou won't be able to unlock another characterTo get himafter the FOREST OF SYMBOL casego to HARLEY and talk to an old man and a guy NPCThey will talk something about dragons in SALVAGo to SALVAenter to the mine and train a bitRun to somewhere when you see BEWARE OF DRAGONSGo through that way and you will see a guy going to slay the dragons tooFollow himThere will be some talkings and press TAKE RESPONSIBLILTYSave your game up too
OPERA-This oneyou can't have ASHTON in your group firstDon't talk to the guy and old man tooOnce you talk to themthe story will trigger and you will fail unlocking this characterFirst go to LACUER and do the tournamentThen go back to HILTON and to the barThere will be a 3-eyed lady thereTalk to herThen go to KROSSE and go for an audience with the kingGet the pass to MOUNTAIN PALACEGo towards there and let the guards let you passThen go to the first split and go NorthThen follow the path until you reach a door and enterContinue downstairs to the right and continue until you reach a savepointSAve and enter the roomGo back to the 4-way splitTake the lower left pathReach a split again and take the upper right pathYou will reach Opera by a plight of stairs

To be continue!