Little is known about Bobo's past. However, Bobo claimed that before he was turned into an E.V.O., he was a helper animal trained to entertain children at a hospital. His owner was supposedly an eccentric philanthropist.
Bobo claims that he's been banned from six different countries for a series of mind blowing pranks he's pulled on them. These pranks got him captured by Providence numerous times but every time he was able to escape.
The final of these pranks, threatening to "push the button" for caviar in Russia, eventually resulted in his capture by Providence. He later met Rex, a young E.V.O. and future secret weapon of Providence, and Dr. Holiday, future head scientist of Providence. He helped the latter out of a jam and this most likely earned him a job at Providence both as best friend to Rex and gun toting field agent.