Raven's Demon

Raven's Demon is a one-time villain from the Cartoon Network original series, Teen Titans Go!, only appearing in the crossover movie, "Teen Titans Go! vs. Teen Titans". She is a demon of black magic, that lives in Raven's mind and slowly tries to take over her body and turn her completely evil.

Biography
Ever since the beginning of the series, Raven's demon has always been trapped inside her mind. However, she did not actually make her first appearance until the crossover movie, "Teen Titans Go! vs. Teen Titans", where Raven's demon was unleashed from her mind by Gentleman Ghost, when he broke the gem on her forehead in battle, unleashing the dark, plague-like demon from her head. Raven's demon would come after Gentleman Ghost and chase him out of her mind. After Gentleman Ghost escaped, Raven's Demon would seep through the cracked gem on Raven's actual forehead and shroud her body in her darkness, taking control of her physical form and using it for her own purposes. Raven's Demon would grow really huge and blast a giant gust of black magic at Gentleman Ghost, obliterating him completely. Raven's Demon then sopped back into Raven's skull again, leaving Raven, lying on the floor, temporarily unconscious. When Raven woke up, she didn't remember anything that happened until Cyborg showed her a video he recorded to show her how cool it was. Raven was shocked with the fact that her inner demon escaped and explained to her fellow Titans that it was not good that this side of her came out. Starfire offered to help Raven fix this but Raven told her that she wasn't half-demon, so she wouldn't understand. Raven fled to her room to try and figure herself out.

Raven traveled into her mind to confront her demon, but when she slipped into the safe room, where the cracked gem was, her demon just snuck up behind her and attacked her. This woke Raven up from her little brain trip and got her to question what was happening to her. She went over to her mirror and looked into it. Suddenly, she started to hear a deep and scary voice, telling her that she needed to betray her friends and become evil. Raven recognized this voice and as she expected, in the mirror, formed the image of Trigon, telling her that he knew what was happening. As he explained, the gem in her head is what contains her inner demon. Now that it's cracked, the demon is coming out and will soon turn her completely evil. Trigon made a deal with her, saying that if she offers to give up her demon to him completely, he could turn her into a normal girl, while he utilizes her demon to take over the world. Raven refused, much to Trigon's disappointment. Trigon told her that the more she uses her powers, the more power the demon will have over her and eventually if she uses it too much, she will lose control of herself completely. Raven just said that she won't use her powers and she broke the mirror to cut off connection with her father. After Raven left, the form of Trigon from the original Teen Titans series formed in the broken shards of glass on the floor and told the Teen Titans Go! version of Trigon that due to his offer not working, they were going to carry out their next plan, which TTG Trigon sadly accepted to do with him.

A giant ship came out of a portal to another dimension and entered the TTG dimension. Some disguised figures dropped from the ship, invaded the Titans Tower and kidnapped all the Titans, bringing them all into an arena. There, they were greeted by the Master of Games, who told them that they were to fight with their kidnappers, who soon revealed themselves to be the Teen Titans from the original series. Both parties of Titans fought, which meant that Raven had to use her powers again, which meant that her demon kept coming out. The more she used her powers, the more a giant diamond in the middle of the arena was getting fueled, much to the unexplained excitement of the Master of Games. The original version of Raven noticed what was going on and stopped Raven's demon before the diamond was entirely full and explained to her what was going on. The Master of Games revealed himself to actually by the TTG version of Trigon in disguise. TTG Trigon revealed that this was his plan all along as he brought out the Teen Titans version of Trigon, who kidnapped both the TTG and original versions of Raven and took them off to original Trigon's evil demon cave.