Mean Mikey is like the original in that he is a vampire, however unlike his original, he doesn’t hide his vampirism, he embraces it fully and feels no shame biting others. Mean Mikey had a falling out with Mean Pete not too long after they were both made, and this broke and upset him so much, he erased as much of him as he could that has a connection to him, including pulling off his wristband and discarding it, scarring his own cutie mark, and tearing his hoodie. He flew far away from him in the woods and uses his bitter attitude on others.
He doesn’t have a lot to say, but the things he does say are carefully crafted to perfectly upset whoever he is talking to. Had a bad day? He’ll know exactly why that is and use that against you to make you depressed, angry, or just really irritated. After whoever he’s bothering is sufficiently upset, he’ll bite them, blood is tastier thanks to negative emotions, and fly away. Sometimes the blood loss makes them pass out.
While most things don’t phase his mood, even so much as just mentioning Pete at all is enough to upset enough into just flying away. Despite not existing for very long as a clone, he already has deep-rooted issues that cripple his emotions incredibly easily, and lacking in the empathy that he does, a refusal to work them out in any way.