Gajeel spun around at the voice, already smirking... and then stopped. And looked in a more down-ish direction.

The smirk got bigger. He hadn't expected much from that voice, but this was even better than he could have expected. "Oh, what are you gonna do? Punch out my kneecaps?" Those cannons looked like they might be a problem, but in the meantime? Small robot, probably not a threat.