Olajide "JJ" Olatunji (born 19 June 1993 in Watford, Hertfordshire, England), also known as KSIOlajideBT or simply KSI, is a YouTube and Internet celebrity, comedian, musician and video game commentator. He has a younger brother named Deji who creates and produces similar content on YouTube. Olatunji is known for his crude, and often sexual, humor. He is also a member of the Ultimate Sidemen gaming YouTuber group, which he formed on 19 October 2013 along with YouTubers Vikram Barn (Vikkstar123), Josh Bradley (Zerkaa), Tobi Brown (TBJZL), Simon Minter (miniminter), and Ethan Payne (Behzinga); they were later joined by Harold "Harry" Lewis (wroetoshaw) in 2014.