>>33273074 (OP)You can grind it for sure. I used to be really awkward and was a come-along friend. I started getting more comfortable with people and realized they liked me when I cut loose so I started doing it more and more. These days I'm a social butterfly and people just randomly strike up conversations with me in public, confuses the shit out of my wife.
You can *also* grind looks though, think of it as a proficiency bonus if you're familiar. If you're unkempt and grubby looking it'll be a -3 to your charisma roll; but if you take the same dude with a haircut and nice clothes it'll be a +2 to your roll. You can roll the dice from 1 to 20, but if you actively look like shit you can only get up to a 17 and if you put the effort into presenting yourself well you can get up to a 22.
I did both and it worked out pretty well.