"It's not food," Rosa said, staring at Zeiat incredulously. "It's a rubber ball."

One that she was now lobbing lightly on the wall, bouncing it back into her hand, and then back on wall, in a smooth, steady suggestion of some sort of disjointed rhythm.

"And I shoot bad guys because it's my job to shoot bad guys. It's not my job to shoot students."

A pause. Another toss of the ball against the wall.

"Unless they're bad guys."