To expand on the idea that Celine and Mi-Yeong fought with each other before their debut that i hinted at in this post.
Mi-Yeong and Celine were always at each others throats. For Mi-Yeong being a hunter was an escape. She lived on the streets since she was ten, being a hunter meant having a home to go back to every night and she would not ruin that opportunity.
Celine on the other hand had a home to go back to. Sure it wasn't the best, her parents would fight often about the tiniest things. Like her father buying pre-ground black pepper instead of whole peppercorns or her mother only making enough coffee for her and not her dad. But they never fought about Celine. Actually they never seem to care about Celine at all; she gets all A's they don't care; she gets caught smoking a cigarette during lunch they don't care. Celine skips school for a week to go to Vegas with her too old for her boyfriend, they don't care. So why would Celine care. She is just doing this because it gets her out of school. It's totally not an escape from her home life.
When they meet Celine and Mi-Yeong are instantly enemies. Celine hates how much Mi-Yeong is a "goody two shoes", she is always there to find Celine "doing something wrong". Celine sneaks out one night to smoke a cig and Mi-Yeong is there lecturing her about her health. Celine tries to summon non weapons from the honmoon and Mi-Yeong is there to lecture her on how she needs to be more respectful to the honmoon and how important the golden honmoon is for humanity. What has humanity ever done for her. It doesn't make sense why Mi-Yeong would care so much, care about her.
Mi-Yeong knows Celine cares, like a lot actually. Even if she tries to hide it. Mi-Yeong can see how attentively Celine wraps bandages on her and Poppy after their first demon battle doesn't go to plan. She knows when Celine thinks she's alone she'll practice singing their songs, making slight adjustments each time until its perfect. She knows that Celine will act like their combat lessons are boring but she actually takes them to heart, always improving her technique. What Mi-Yeong doesn't understand is why Celine tries to hide it so much. Celine clearly cares about this and them but she refuses to admit it. Some days, deep down, Mi-Yeong feels like she is the reason why, that she isn't good enough to care about.
So the next time she finds Celine sneaking out of the compound she lets her fears get the best of her.
"Why are you sneaking out again?!" Mi-Yeong yells from the door. Already trying to hold back tears.
Celine stops in tracks and looks up at the sky, thinking about how wasted she was going to get at the bar, before turning to face Mi-Yeong. "Because I want to." She answers in a flat uncaring tone.
"We have a photoshoot tomorrow morning, why are you risking missing it. You are supposed to be our leader." Mi-Yeong's voice is starting to shake and her grip on the door is getting tighter.
"If you care about it so much why don't you be our leader then." Celine snaps back. Even from 50 feet away she can see the tears starting to stream down Mi-Yeong's face. She doesn't want to deal with this, doesn't want to see the hurt she caused, so she turns to leave.
Mi-Yeong, her knuckles white from their grip on the door, yells out in mournful panic "Why don't you ever care about anything?!" She knows its not true, Celine does care but right now her pain is stronger than restraint.
Mi-Yeong's accusation is like sandpaper on her heart. Celine reflexively yells back "That's not true. I can care if I want to!"
Before Mi-Yeong can stop herself she cries out, "Then why don't you care about me!" Her vision is totally blurred from her tears now. She refuses to wipe them away, afraid of the web of feelings she just cut through.
Celine feels her heart ripped out of her chest, her blood slowing to a stop. She can barely think before she stutters out, "Mi-Yeong... I... I... that's not..." Mi-Yeong slams the door to the house before she can finish. Celine is frozen, her heart on the ground in front of her. she's alone, again, with only the crescent moon's light providing any proof that she's still alive.
It takes Celine 15 minutes to go back inside that night, her plans in town long forgotten. The next morning she's away before everyone else and has coffee and breakfast ready. It's not a real apology, not even close, but its a step in the right direction. Something to show Mi-Yeong that she does care, even if she can't say it just yet.
Things get better after this, Celine starts to be attentive to her duties as a hunter and an idol, Mi-Yeong starts to relax a couple days of the month. She even asks Celine to take her for a ride on her motorcycle. That is until it happens.
The day Mi-Yeong and Poppy die is the worst day of Celine's life. Her sunshine was gone and all that was left was baby who's existence wouldn't have happened if Celine didn't teach Mi-Yeong how to relax. Those happy, laid back days where Celine would just play with Mi-Yeong's hair as they listens to Poppy yap about Cowboy Bebop were no longer a happy memory, they were the cause of her loves deaths. So Celine does what she "should" have done a long time ago, she makes everything about being a hunter. Celine molds Rumi to be the perfect hunter so that Mi-Yeong's goal of making the golden honmoon can be made a reality. And Rumi's patterns well those are just proof her mistakes so Celine tells her to cover up, she can't stand to be reminded of all the pain she caused.
Its not until after the Idol Awards does Celine go to therapy, from her childhood to her parenting of Rumi everything is gone over. She learns how to deal with her emotions and apologizes to Rumi and the girls for everything. And eventually it feels like a weight has been lifted from her shoulders. She finally takes the bike out for a ride after 25 years, she starts writing music again, she goes to events instead of staying back stage. She starts living again.
Rumi, while a little upset that her eomma is kind of cool now, is very happy for her. Seeing her with a real smile on her face is nice. Zoey is over the moon that she finally gets to meet the part of Celine that influenced so many headcanons in the SLS fandom. And Mira finally has a mother figure to look up to. The four of them regularly get dinner together where conversation is about their lives outside of demon hunting and being an idol.
tagging @t4ffyc4t because her ask started all of this and @djinnjin for inspiring me to go deeper into this topic.