Hi, I got my first tattoo on my ribs actually twice cause it had to get touched up and he went over the whole thing. It doesn’t hurt that bad really only feel it in a few spots. Also I would just make sure you are in a comfortable position mine kinda wasn’t just let him put me how he wanted...was hard to keep balance.
Another good thing about ribs is it’s almost always covered. Gives you time to warm up to the idea you are tatted and become comfortable with showing it as you please. You should definitely go for it