Copper as Killer!Sans.

Copper was injured and his arms and legs had ripped off, he was possessed by the demon and Rinny, before he cannot move, he found a bionic mechanical arms and legs, so he was a murderous psychopath to get away with Elma.

Bloon was betrayed and killed by Copper to treat him like a troublemaker, so he was a forgotten figure to guide him before Copper was not stupid to mock him.

Good ending: He successfully get out from Rinny out of his control, and after he needs to be good and helpful but what he has done of his guilt.

Bad ending: He's gotten insane and she's really in control to torture some Malino's, including Elma.

Information about him:

Masochist was a bit smart, but neither a dumbass at the same time.

He loves torturing just like Rinny.

The bionic mechanical arms will attach to change into a blaster, arm cannon, chainsaw, sword and so much more to take.

He could use his powers with a lightning bolt, filled with dark red, he could do use a shockwave and a red rainstorm.

The bionic mechanical legs were decided to fly high, and kicks really hard.

He was a sinner, still a gay and still was a femboy.

Likes to mock and annoyed a lot, but if you think his IQ was better to his ego.