Rob & Big star Christopher “Big Black” Boykin died on Tuesday, May 9. His rep confirmed his death to TMZ, but no cause of death as been released. The reality star was 45.

“MTV is deeply saddened to learn the news of Christopher ‘Big Black’ Boykin’s passing,” an MTV spokesperson told Us Weekly in a statement. “He was a long time and beloved member of the MTV family and will be greatly missed. Our thoughts and prayers go out to his family and friends at this time.”

Boykin appeared as Rob Dyrdek’s best friend and bodyguard on the MTV reality show, which ran for three seasons from 2006 to 2008. Watch some of their best moments from the show in the video above. The series documented the two friends going on random adventures and goofing around. He also appeared on Dyrdek’s series Fantasy Factory.

During a March 2016 interview, Dyrdek opened up about his fall out with Boykin. “He didn’t want to be known for [being] the sidekick,” the professional skate boarder explained. “So that created a lot of that tension between me and him.”

Prior to making a name for himself on reality TV, Boykin served in the Navy. He is survived by his ex-wife, Shannon, and their 9-year-old daughter.