Since he has the same thing that CW Jon has (by complete coincidence spARE ME-) which is dissociative identity disorder /DID. Also I gave Jon three sides now so.. Yeah-

Jon- His actual side. Jon Hyde. Jon is a sweet sorta mother figure friend who wouldn't dare hurt anything. If he did. It'd be by accident or because of his other sides. Jon has a very negative reaction towards abuse, but he isn't afraid to talk about his issues. He doesn't like keeping them all to himself. He talks to people he trusts, though. He is also extremely sensitive, so if you said something bad, more likely he'd cry. He tries to not let it bother him but it's hard. Jon has a horrible relationship with his mother and a great one with his father and brother, Don. He sometimes self harms if he starts having a really bad time with dealing with the voices and the feeling of just detachment. But most of the time he covers it up and tries to make sure everyone is fine. This makes him pretty selfless.

Jack- Jack is basically the opposite of Jon. Jack Jekyll is a very loud person. If something bothers him, he is loud and straightforward with the issue. Since Jon has long hair, Jack often ties to to the side to get it off his neck. He hates stuff touching his neck. He doesn't cover Jon's scars, he doesn't give a shit about them. He is much more into blood, hence why he murders. He would hurt anyone that is considered a victim to him. He never touches his friends though. He loves his/Jon's friends. He acts more like a joking father figure then a sweet mother figure. He often is seen with a glass shard, because he thinks knives are very cliché. So he never uses them. He uses things that others think is just different, which is a glass shard. Sometimes he even uses a shard from a potted plant. He is a bit more sassy too, a lot more attitude. If you want him to cry, just say something about Jon's mother being great or something to do with her. He'll be angry and crying because he was made to protect Jon from his mother.

Joan: Yes. Joan. Not something like 'Joan of Arc' but just Joan as in, the Spanish male name. He doesn't sound Spanish but his voice is definitely deeper then Jon's and Jack's. He sounds extremely monotone at times but sometimes he sounds so sadistic or sinister. He's worse then Jack. Yes, he protects Jon, but he can cause some bad shit to make sure Jon is alone, which is more for protection. He will attack his own friends for no reason but this only goes on for at least a couple minutes or he needs to be knocked out. He doesn't want Jon to be close to someone then suddenly they hurt him, so he basically pushes everyone away. Unlike Jon and a bit of Jack, he didn't like Todd at all. While Jon didn't mind him and even liked him and Jack just thought he was stupid, which amused him, he wanted Todd out of the picture. It is very hard to gain Joan's trust, the only people who have is Todd, his father and animals. Since Joan isn't a murderer against animals. He does murder as well, but it's only when people try to befriend Jon randomly or someone says something rude, he won't even talk about it like Jack, he'll just attack you. He often uses a katana to kill his victims, since it's so much longer and it can easily pierce through someone, he thinks, so he uses that.