B403 - B401’s sidekick, but it’s also its nemesis, like when your f

B401’s sidekick, but it’s also its nemesis, like when your friend borrows your pencil and breaks it.

B403 is B401’s sidekick, but also its enemy.

B403 is like B401’s friend who always steals your snacks.

B403 is B401’s annoying brother.