Tight lacing with a corset can help reduce the size if your bottom two ribs, or floating ribs as they are called. They are called floating ribs because they are attached to the spine, but not the sternum... Which means they can be bent inward. The younger you are, the more malleable your body is, and thus the easier it is to bend your ribs.
In the case of rib removable, since your ribs are cartilage, then it's possible that they can grow back after removal. This typically doesn't happen, but certainly is possible. For removal, the doctor would go in through your back and simply saw the ribs off near the spine. The recovery and pain would be horrific, but obviously, it is manageable. The scar from the surgery will be very noticeable. This surgery typically isn't done for cosmetic reasons, and you will find a tough time getting a reputable surgeon to do this procedure.
Lastly, there is a condition involving the sternum known as pectus excavatum, which is much more likely to occur in males than in females. This condition is noted by a dip in the center of your chest, sometimes a small dip, sometimes a very large dip. This is caused by tendons and bones growing at different rates during puberty, and consequently, as your chest dips in, your ribs bow or flare out. In most cases the condition doesn't pose any threat, but in more severe cases this condition will interfere with your breathing or even your heart... Which would make it a medical necessity to be fixed under insurance.
