What happens once you remove a dangerous/harmful mole?
First, I am assuming this was not a skin cancer, right? If it was just a benign mole that was harmful by its location or symptoms or a dangerous (pre-cancerous) mole, nothing happens except healing of the site and conversion to, hopefully, an acceptable scar. If the mole was pre-cancerous, you need to be checked for others periodically (every year or so) by a dermatologist.
Avoid the sun, also.