Dropkick really didn't want to come to lame old Earth, but Megatron made him. If he had his way, he'd be back on Cybertron right now, sitting alone in the dark and feeling angry. He doesn't really "get" why folks are so interested in the AllSpark or why the Autobots are such troublemakers, but he DOES like making things go BOOM, so he might as well do so while he's here.
He seems kinda emo. Go cry, emo robot.
Sometimes there are lots of him.
On both sides.