It was a wary, uncertain moment in which Bob took up the cans. L didn't have much time to react when the cans were flung at his bony torso; his automatic reflex was to protect his head and brain, which only exposed Bob's actual target even more.
He was only able to dodge one, the other three cans hitting him in various painful places, battering his ribs, sternum, and the painful place just above his stomach. It was enough to cause him to double over, gasping for breath... but he held tightly to his lighter and can of aerosol, hiding them under his crumpled, hurting body as he lay stomach-down like a crushed frog. L was difficult to outwit, but fairly easy to injure, and he'd be tremblingly trying to catch his breath for at least a minute.
However... it was a not-quick stop, and the space under and behind the counter was cluttered. There were a few old and leftover fireworks leftover from some long-past Fourth of July, it seemed. Lighter in hand, L very carefully lit one of the smaller rockets, keeping it hidden from view for the moment. It was aimed at an angle toward the ceiling. Whether Bob moved or not, it wouldn't hit his tubby girth, but it would certainly be loud and startling. Hopefully, enough for L to get away.