If your firearm is truly concealed while you carry, your "friend" would have no knowledge of it. If his right to own a firearm is gone due to his felonious actions then it is HE who cannot carry the firearm.
However, let's play a little scenario. You have your gun in the console (not locked). You then get pulled over by the police for something minor. If the cop asks you to step out of the car, you then are leaving a felon in the car with a loaded weapon. If that scenario happens, how will you proceed? "Excuse me officer, before I get out, I have a loaded weapon in the console and a known felon in the next seat... ummm, what do you want me to do?"
Just keep it on your person, if you don't already do so.