Obbo

Obbo was a drug dealer (he supplied heroin to Terri Weedon) and seller of stolen goods (he fenced a batch of stolen computers, one of which was bought by Simon Price). He was also a rapist, and possibly involved in other crimes as well.

Behind the scenes
"Obbo" is almost certainly a play on the British English term "yobbo" meaning a thug, especially a teenager or young adult. It is probably a nickname rather than a proper name.