The Virus use to be a body guard known as Corman, in AGK inc. AGKs directors had killed dozens or hundreds of people, when they tested how to create a superhuman, by using nanites.
Only one survivor, Tara, got superpowers. Tara and Spider-man found out about the crimes of AGK, and fought against Corman. As the result of the fight, Corman was covered with nanites, and he became The Virus.
He said that he had a deep connection with Spider-man. The way Venom has.
He escaped to an unknown location. Even though his last known words implied a return, he hasn`t been seen ever since.