Bannon is the annoying, pretentious knobhead who runs Potomac Attire in Tetanus City. He seems hell-bent on welcoming you to Potomac Attire even if he's standing outside the marketplace and you're standing in the hallway. He is such an arrogant wanker that it leads the player to side with Seagrave Holmes on principle.
It is highly amusing to visualise him in blown away in pieces all over the Rivet City market, and even more fun to actually make it happen. The recommended instrument of destruction is, naturally, a frag grenade, or a plasma dildo (the latter of which is extremely rare) .
The player character, aka the player character, (sometimes even known as the player character) should know that Bannon is not very sexy and extremely black.