Gotta ask about that part of Kokichi's origin in the precure story, did Monokuma almost get him? If not then I wonder what happened to him when our main heros defeated him.
Okay, so Kokichi started out trying to trick Junko into revealing weaknesses and/or leaving his kingdom alone by pretending to be on her side, but over the years he started to actually buy in to her worldview. Her magic is kind of corrupting/mind controly, but it was Kokichi talking himself into doing more and more bad things and becoming more and more disillusioned with the Precure as he sees Rantaro and Tsumugi fail that really kept him as a villain. (As a child he really believed in the Precure, and kind of wanted to be a Precure or Precure fairy. But he wasn’t chosen.)
Then Dam manages to get into the Evil Junko Dimension (I need a real name for this…) because he senses Kokichi is a Precure. And Kokichi is so pissed that he would dare show up then, when everything has gone to shit and Kokichi no longer believes. So, the dark/corrupted Precure thing isn’t really Junko-based, unlike Tsumugi’s. Like, she created the situation, but he did it to himself.
This becomes relevant when the four Precure manage to win against Kokichi and hit him with a group finisher. He’s forced back into his “civilian” form, and then his villain costume fades away, so they think they’ve won! Then he transforms back into his evil Cure form anyway.
The other Cures get pulled off into sort of mirror dimension things (like, a void full of partially broken mirrors with silhouettes representing different points in Kokichi’s life, parts of his personality, etc.), and he keeps jumping between them to fight/taunt them for thinking they’d won. But the mirrors are revealing more than he wants about his feelings, and the Cures individually realize that they can’t beat him with brute force. They need to get him to acknowledge his issues and ask for help, like they all did.
Shuichi and Maki are kind of unsure about how to reach out to him. They kind of empathize with some individual parts of his experiences, but they don’t have all the details, and don’t feel qualified to address weird magic trauma. Luckily, Kaede and Kaito are super ready to stick their noses into other people’s business. They’re also not quite sure if they’re doing it right, but that’s not gonna stop them from trying!
Both of them get more effective as they see how the silhouettes react, and more mirrors keep breaking. (Shuichi and Maki get in on it eventually.) Kokichi is less willing to listen to Kaede since she reminds him of Junko and Tsumugi. He sort of assumes Kaito won’t be able to understand him at all, so it’s safe to keep going after him, but somehow… Eventually Kokichi actually admits he has problems (i.e., breaks down crying) and lets Kaito get close (i.e., cooldown hug).
This actually purifies the corruption, at which point the mirror dimensions collapse, and the whole team is together. Just in time for the villains to notice they’ve broken in. Meanwhile, the fairies have been tracking down Dam, and manage to free him. They all (fairies and Precure) manage to escape back to the human world before Junko or the other villains catch them.
At this point, they try to get Kokichi to go to school, but can’t make a convincing argument that it would help him in the future, so he just kind of wanders around trying out weird human things and learning from the internet. Also, they decide he has to stay with Kaito since he’s the only one who lives alone, and this predictably goes Badly. Especially since his apartment is essentially one room, critically with one bed. All the others eventually offer to let Kokichi stay at their places instead, since it seems like both of them are fighting so much. They both refuse.
