His name is Charles, Charlie for short. He has hair that imitates blue slime and often drips in his face. He has a normal arm and then he has an arm made of the same substance as his hair and it can morph into random things. He's really nice, but is vey shy. He rebeled from the family and became a killer known by the name: *I haven't decided yet, I'm thinking something like The Dripping Killer.
Maybe we need a bit motivation for why he would be a killer. I always imagined him as this nice yet shy person but he puts on a shell of confidence and tries to be inspiring, but doesn't actually think he's good enough to be in a role of importance.
Also we need to align him to Lunos via some genetic features so they all kind of seem related
The hair and pale skin, both their hair colors are similar shades of blue
The killer part I think was him trying to protect his family from people like their parents, who were abusive?