VIDEO : Justin Bieber ?Couldn?t Care Less? If Kourtney Kardashian Is Using Him

Justin Bieber isn?t sorry about his fling with Kourtney Kardashian. Word has it that the 21-year-old singer is thrilled that Kardashian, 36, is into him ? even if there?s nothing serious going on between the two. ?He has had a huge ego boost from hooking up with Kourt. It?s been going on for a few months,? a source tells People. Someone close to the situation claims the mom-of-three is just focused on having a good time.