Well, you might wanna sit down for this. These apes traveled to Unova to capture a powerful pokemon to free their dark master in the Convexity. Melody was the one captured. They forced her to do horrible things by making fight other pokemon to make her aggressive and powerful than before, but she refuses to do it. She's gentle and friendly, but she will fight back if someone, or something tries to kill her. So instead of forcing her to fight, they chained her up and corrupted her by using the Dark Master's powers, brainwashing her to do the apes and her master's bidding. It's how she got her corrupted form. After she was freed, she happens to never trust these apes, instead of being nice to them, she kills them. Despite never trusting them and killing them, she regrets doing this, she lost her innocence to these apes. She has now PTSD from these apes. She still has it to this day.