These are personalities which pertain to some trait about the character (eg. Suzette has a "Sweet tooth" personality because she loves sweets, "Eastern" personality characters come from the East, etc.). Multiple characters who have the same personality trait (other than Miner and Forager) can activate a special combo attack, if they are in the active party at the end of a full Another Force attack.
Weapon Type Personalities
All characters have personalities which correlate to their weapon type as well.