The term used to describe the synergy between Wolverine from the X-Men series and Akuma from the Street Fighter franchise in the crossover fighting game "Marvel vs Capcom 3: Fate of Two Worlds." This pairing is one of the most powerful pairings in the entire game, hence the name "best friends forever."
Man 2: Man, it's the best friends forever. Too bad he's facing off against a Phoenix team; he should have used that Tron for the Level 3 grab and drill assist...
A best friends forever club is a group or 3 or more people that consider themselves best friends. They cant be best friends, cause there are more than 2 of them, so they become a club.
Richie, Jessica, and Andrea are in the best friends forever club. They always sing this cute little song