Fuckin' Best Friend
Similar to BFF but without the girly connotation. What you'd call your best buddy who you know will stick with you through thick and thin. You look forward to hanging out and doing shit with them and there's always better things to come. Even when they've gone someplace far away it still feels like they're there with you. They're not just your best friend, they're your fuckin' best friend.
AT: Hahaha that was pretty crazy. Gotta run now, have a good one FBF
MY: See ya later, my FBF