Raymond Maxwell Jensen was kind of a loser. Losing three jobs in a year he finally landed a handyman job at a government lab. When Superman carried out some experiments at the lab with radioactive materials from space he had some leftover crap. Jensen was assigned to dispose of this material but, being a little larcenous, supposed that anything that had Superman's attention mighty be worth something. When exposed to the radiation he was hideously burned and turned into a human atomic furnace, burning up energy at a ruinous rate. If he hadn't absorbed energy from people around him he would have perished. Then he decided that if he really wanted a good feed he should go after Superman. He did but Superman possessed so much energy that this human parasite disintegrated because he couldn't absorb so much so fast. Of course a good villain doesn't just go away that easily so an alien encountered his energy signature and reformed him - only physically, not morally. So the Parasite has made a number of comebacks and probably will continue to do so. I used a Toy Biz Silver Surfer figure for the conversion, which basically amounted to a paint job.