Bobby is a supporting character in the Spawn comics.
A veteran of the Vietnam war ,Bobby became homeless after his return to the United States. It was many years later that he met and befriended Spawn, the current Hellspawn. Unfortunately his friendship with Spawn would indirectly caused his death. Soon after Spawn had attacked and branded Chapel he sought revenge and killed Bobby in a fight against Spawn. He then committed suicide in an attempt to receive the same powers as Spawn. Spawn however used a vast portion of his powers to revive body but all the while bringing him closer to his own "death". After being resurrected Bobby was kidnapped when the second Redeemer was sent to capture him. As soon as Redeemer found him he began to study him keeping him in a field of energy covering him with a sticky yellow material. When Spawn tried to save him he was knocked out and Redeemer teleported away with Bobby in tow. After Spawn recovered his suit went through it's first metamorphoses. With his new found suit he attacked Heaven's Terran Base in an attempt to save Bobby. When Spawn forced them to send down Bobby he battled Redeemer and the forces of heaven eventually being forced to escape by teleportation and sent Bobby and himself back to the alleys.
After Spawn had forced everyone to leave the alleys of rat city in later events, Bobby disappeared and hasn't been heard from since.
In the tv series
Bobby is more difference in the cartoon series.