Incest is a taboo and illegal form of sexual activity that involves sexual relations between close blood relatives, such as siblings, parents and children, or other close family members. Incest is considered harmful and unethical due to the potential for genetic abnormalities in offspring, as well as the power dynamics and potential for abuse that can exist within familial relationships. It is important to seek help and support if you or someone you know is experiencing or considering engaging in incestuous behavior.