After naming the main character, but before the first cutscene, the player can bring up the character order screen and move one of the remaining three undefined characters into the first slot—this prevents the normal selection of name and species that would subsequently occur (the main character is instead selected twice, with the second selection overriding the first).
Although the placeholder characters look like the monster Fungus (and are listed as such on their status screens), for all gameplay purposes they act as human characters do. They cannot eat monster meat, can equip weapons and armor, and their stats increase after battle in the same manner as humans.
All of their stats including hit points start at 0. A character with 0 maximum hit points will become Stun if they take any damage, though being healed has no adverse effect. Like any character that ends a battle with 0 HP, a human fungus will be restored to 1 HP afterward, even if they were not actually stunned. If the player visits an inn while such a character has 1/0 HP, the cost to stay at the inn will be one less than normal; if the cost would be 0, it is instead 65535 due to negative overflow.