Extremely Low Charisma Character

[Vogar Eol]

If we really want to talk about an ability, we need to consider what the two extremes are suppose to do in source material. Every stat has a special thing that happens if it hits zero.

Zero Strength? You lay motionless on the ground like a jellyfish on a beach, unable to move.
Zero Constitution? You're dead.
Zero Dexterity? You're ridged and immobile, stiff as a board, unable to move.
Zero Intelligence? Impossible to think, and lays in a coma-like stupor.
Zero Wisdom? Trapped in a nightmare filled coma-like sleep.
Zero Charisma? Withdraw into your own mind, and become catatonic.

Since we know some examples of extremely High charisma, and we know what Zero charisma does... we can create a slider between those two extremes. In the case of charisma, I see those two extremes as the difference between Winston Churchill, and a catatonic person in a nursing home or sanitarium. What's one ability modifier up from a Sanitarian Catatonic? Probably some severe form of Autism or other social/mental disability.

I'm reminded of when Teris threw mushrooms at people.