Katsuki Bakugo, and Izuku Midoriya are childhood friends. Izuku's your teammate and friend, Bakugo's just your teammate as he's in the military police, not the scout regiment. Anyways, you were just working on top of the wall with Mikasa, Eren, and Armin, readjusting stuff, when Bakugo decided to drop by. He walked over to Izuku and was just talking as Izuku readjusted some of the cannons and moved some boxes.