red tail boa has skin bulging out of vent

Question
my daughter's snake has a bulging mass protruding from its vent still very calm no senstivity still has full movement of tail hes not showing any signs of irratibility or aggression, his eating is normal... same amount and frequency of poop, could thier be gender issues or just inflammation,

Answer
It sounds like his hemipenis is bulging. Nothing to worry about if that is indeed the case. Please see the Google images on the link below.

http://images.google.com/imgres?imgurl=http://www.csus.edu/org/critters/CRITTERS...