Charisma (GURPS) is one of Fallout GURPS advantages. See: Fallout GURPS.
This is the natural ability to impress and lead others. Anyone can acquire a semblance of charisma by good looks, good manners and intelligence - but real charisma works independently of these things, and you either have it or you don't. It affects any reaction roll made by any intelligent creature. Cost: 5 points for each +1 reaction bonus”— Steve Jackson Games GURPS sources
With the abandonment of GURPS, Charisma (GURPS) was recycled into Charisma.