(Flashback, 5 Years Ago)
Even though Christina had stopped hanging out with him, Y/N's reputation still stuck with her by the rest of the school. Christina was walking in the hallways when she overheard nearby chatting by nearby students.
Random Student #67: "Look, it's her. Y/N's sister."
Random Student #19: "More like lapdog."
Random Student #55: "Well, not anymore. She's been by herself lately."
Random Student #34: "I wouldn't be surprised if she was disposed of. Guess her little ideas aren't doing him any good."
Random Student # 41: "Wow, Y/N is so ruthless. He really doesn't care about anyone who isn't useful to him, huh? Not even with his own sister."
Random Student #35: "Psh, well I don't feel bad for her. I mean, isn't she the one who made him like this to begin with?"
Christina kept quiet as the chatting and whispering continued.
Random Student #35: "It's her fault the school's such a mess!"
They weren't even wrong. Omen Academy was in shambles because of her helping Y/N become this powerful. She created a monster. As she cried to herself, she wanted to stop Y/N so badly, but she didn't know what to do. What can she do? Talking won't do much and even if she trains her semblance to be strong and fight him, the fight would be over once Y/N mimics it. Until she thought of an idea. It'll be difficult to do, but at this point, she's running out of options. And if things go well, she'll have a chance of getting through to him after all.
(The Next Day)
As soon as the school day ended, Christina went to look for Zayden. She rushes through the hallways as Darius takes notice of her presence.
Darius: "Hey, Christina! It's been a while!"
Christina didn't respond as she rushed through the halls, much to Darius's confusion.
Zayden is walking through the hall until he heard a voice behind him.
Christina: "Zayden!"
He turns to see Christina, panting from running.
Zayden: "Huh? What the hell do you want?"
Christina: "I want to help you take Y/N down."
Zayden: "What? Is this some kind of prank or something? Sheesh, get a life, weirdo."
Christina: "No, I'm being serious. I know that you and everyone else have had enough of Y/N. I don't want him to continue like this either."
Zayden: "Who are you trying to fool here? If I remember correctly, you're the one who helped Y/N get to where he is in the first place."
Zayden then narrowed his eyes, staring down at Christina.
Zayden: "In fact, give me one reason why I shouldn't beat you up right now."
Christina knew he wouldn't believe her easily, but she was determined to convince him somehow. So, she had to lie.
Christina: "Last night, I had this dream that the two of us teamed up and dethroned Y/N."
Zayden went silent for a moment.
Zayden: "So... You're really plan on turning on him?"
To Christina, she was the one who caused all of this, so it was her responsibility to put an end to it for good.
Christina: "... That's right..."
She looks down only to look up again to face the former Hero.
Christina: "The thing is, I want control more than anything else! I haven't told anyone this, but I knew exactly how strong Y/N would become long before he attended Omen Academy. So, I took advantage of him while he was still weak."
Unbeknownst to her and Zayden, Darius is hiding around the corner, listening to their conversation.
Darius: "..."
Christina: "I thought that if I helped him early... He'd stay loyal to me, his big sis, no matter what. But it looks like I was wrong. He went and got a mind of his own."
As Darius overhears their conversation, he slides down, sitting against the wall, upset to hear this. After a moment of sitting, he gets up and rushes over to where Y/N is at.
Zayden: "So that's the kind of person you are? And all this time I thought you and Y/N care about each other. Turns out you were just using your own brother. The moment you find a better option, you'd just stab him in the back?"
Zayden looked at her with a look of disdain.
Zayden: "Wow, you're disgusting. No wonder you two and that other kid are called the Terrible Trio. You and your brother are power-hungry snakes."
Christina said nothing to his comment as she clenched her fists.
Chrisina: "Zayden, please work with me. We'll defeat Y/N and take control of Omen Academy for the better."
Zayden went silent for a moment before he could respond back.
Zayden: "I swear, if it weren't for the fact that Y/N was running this school into the ground, I'd never associate with someone like you."
As he begins to walk away, he continues to speak.
Zayden: "I'll need time to think it over. I guess we'll be in touch."
As he left, Christina continued to stay silent. She did it, but she must endure a bit more if her plan to get through to Y/N will work.
__________________________________________________________________
Later, Christina, Zayden, and a group of other students are waiting for Y/N to show up via the letter she gave him.
Random Student #33: "Ugh! What's taking so long?!"
Random Student #12: "Yeah, I'm sick of waiting right now!"
Getting a bit annoyed, Zayden looks towards Christina.
Zayden: "Hey! He better show up! I didn't bring all these people here for nothing."
Christina: "Don't worry. He'll show up."
She looks toward the other students.
Christina: "Remember, everyone! When Y/N gets here, be sure to not activate any of your semblances! We'll talk to him first!"
As she said this, the rest of the students groaned and grunted as they looked at her in annoyance.
Random Student #23: "Jeez, shut up already!"
Random Student #27: "Why do we have to listen to her again?"
Random Student #41: "Does she even know what she's talking about?"
Regardless of what they say to her, she continues.
Christina: "Fight only if we have to!"
Y/N: "Christina? What the hell is this?"
Christina looks at him, her expression serious and her brows narrowed.
Christina: "Y/N, I called you here because I wanted to show you this."
She motions to Zayden and the other students, all looking at him angrily and in disdain.
Christina: "This is a fraction of the students who have been mistreated under your leadership. We've all had enough of your abuse! You're hurting too many people! It's time for you to stop, Y/N!"
Y/N: "So... You really went and did it, huh?"
Y/N becomes visibly angry and begins to shout.
Y/N; "You backstabbing bitch! You really rallied people behind my back!? And with that jackass too!?"
Zayden: "Actions have consequences, punk!"
All students: "Yeah!!
Christina: "You idiot! Why can't you just understand already?!"
Y/N: "Oh, shut the hell up! You're the idiot! All of you are fucking idiots! You think banding together against me would do anything! Hah, weaklings like all of you could never take me down! If you think you can, then come at me!"
As he said this, he prepares to fight by taking a stance.
Random Student #19: "I knew it! Talking won't do shit with this guy!"
Random Student #39: "He's not going to listen! He never has!"
Zayden: "Whatever, we have the numbers! Let's just beat this whining bitch up!"
Christina turns to the other students.
Christina: "Wait, no! He's just provoking you guys on purpose! It's part of his strategy!"
As she said this, all the gathered students charge at Y/N.
Christina: "Wait! Don't fall for it!"
Random Student #47: "Who cares? He can't beat all of us! Get him!"
Christina watches in horror as all the students get closer and closer towards Y/N.
Christina: "Everyone, stop! P-Please!"
Her fear heightens more once she sees Y/N activate his semblance via his red eyes, visibly angry. What she didn't expect to see was Y/N's red and black aura becoming visible. Coming out of that aura, were shadow-like wolves with bright red eyes. As the red-eyed Y/N charged at the students, so did those wolves. Most of them severely underestimated him. The moment they activated their semblances, it was over. He was too strong for any of them to stop. And just like before, all she could do was stand and watch as he and his group of shadow-like wolves demolished everyone. Her plan had failed. There was no bringing him back. After a while, Christina falls to her knee, staring at the ground just as Y/N finishes brutally defeating everyone, using Grimm Slayer he got back from Zayden. The shadow-like wolves slowly evaporates as he stands in front of her, looming over her as he stabs Grimm Slayer to the ground.
Y/N: "Christina... Why did you turn everyone against me?"
Christina kept silent. Enraged with her lack of response, Y/N then grabs her by the hair.
Christina: "Ahh!"
Y/N: "Answer me, damn it!"
Christina: "You turned them against yourself! Have you seen yourself!?
Y/N went silent, still holding her hair.
Christina: "L-Let go!"
She managed to free herself from his grip, pushing his arm away, then proceeded to slap him on his cheek.
Y/N: "...!?"
Christina: "Take a good look at what you've become! You're always looking for reasons to hurt others, even when there's none! You don't care about anyone but yourself! You're just a tyrant and a hypocrite!"
Y/N: "You-!"
Christina: "You don't deserve any of the power you have now! Darius and I should never have helped you!"
As she said this, both Y/N and Christina have tears in their eyes and Y/N quickly respond.
Y/N: "S-Shut up!!"
Christina: "Make me then! Go ahead and beat me up like you did with everyone else! You think what you've done makes you a hero, then you're wrong! You're worse than any Grimm!"
Y/N grabs her by the shirt, readying to punch her.
Y/N: "I said... shut the fuck up!"
Christina looks at him, a mixture of anger and sadness on her face as she said her final words.
Christina: "You're a monster."
Eyes widened, Y/N then punched her face, knocking her out.
__________________________________________________________________
A few moments later, Christina could barely hear anything and see anything with her eyes still being hazy. Very slowly, Christina regains consciousness as she overhears the noises around her. She soon realizes that she's inside an empty house with an unconscious Darius nearby. Wanting to know where this noise is coming from, Christina peer over a small hole in the wall. Her eyes widen upon seeing Y/N using his semblance to launch her parents towards the claws and jaws of a large Grimm, which starts killing them in front of him.
Christina: ("No... no... why... why would he...")
Injured and still lying on the floor, Christina begins to cry as she covers her ears, not wanting to hear the screams and roars coming from outside.
Christina: ("Please... someone... anyone... help me...")
The only thing she can think of is Y/N as anger and sadness swell up inside her.
Christina: ("I... I hate him... I hate him so much...")
Suddenly, the door of the empty house begins to open slowly, which caught Christina's attention. She turns to see something she never seen before.
Christina: "What the...? A Grimm...?"
???: "Hello, child..."
Christina is taken aback by the sudden voice of a woman coming out of this particular Grimm.
???: "I sense such intense sadness and anger inside of you. Especially for someone so young..."
Christina: "W-Who are you...?"
Salem: "My name is Salem."
Christina: "S-Salem-"
Before she can finish her sentence, her adrenaline begins to drop as her body fall to the floor with a thud. The last thing Christina could see is the Grimm, looming over her and Darius.
Salem: "Please, let me help you... the both of you."
Christina's eyelids become heavy as all she could see was complete darkness once more.
(Flashback Ends, Evernight Castle)
Darkness and silence are the only thing Christina could see. Soon enough, she starts hearing the growing noises of screams and Grimm roars. Those noises are only overshadowed by Y/N's voice growing louder and louder.
Y/N: "Christina... How dare you betray me... Christina... I never want to see you again... Christina... Christina!!!"
Immediately, Christina jolted up from her bed, eyes widen and breathing heavily. She looks around to see her room to keep her mind at ease as the door to her room opens, revealing to be Salem herself.
Christina: "Mistress, what brings you here?"
Salem: "Just came here to check up on you. And, we have our meeting with the others, remember?"
Christina: "Ah yes, I'll get change."
She then gets out of her bed and goes to change her clothes before turning back to Salem.
Christina: "Uhm, Mistress, is it true... Darius is... dead...?"
After a couple moments of silence, Salem responds back.
Salem: "Unfortunately, that is correct. Killed during Cinder's master plan."
Christina: "Was it Y/N... did he killed him...?"
Salem: "He did."
Clenching her fists and gritting her teeth, Christina's calm expression turn into rage and sorrow upon hearing Salem's response. Once she finishes changing and grabbing her weapon, she walks up to Salem before bowing to her.
Christina: "Mistress, if I may be so bold, but when do we get to kill Y/N?"
Salem ponders to herself for a moment before replying.
Salem: "You'll get your chance, Christina. You still need to keep training your power."
Christina: "But I've been training for five years now. I should be strong enough to take him down now."
Salem: "You and I both know that he won't be taken down that easily. Besides, we need his power to achieve my goal."
Christina looks down at the floor, visibly upset. Salem let out a sigh before placing a hand on her shoulder.
Salem: "You'll get your chance... you just have to be patient. Once I get what I want from him, I'll leave him to you, okay?"
Slowly, Christina lifts her head up to meet Salem's gaze.
Christina: "If that's what you wish, Mistress, then... I yield."
Salem offers a warm smile to her, giving her a hug for several seconds before letting her go.
Salem: "Good. Now, shall we?"
Christina nod to her in agreement. As Salem leave her room, Christina turns around to get her Grimm mask, a gift Salem gave her, as she put it on.
She then follows after Salem to the meeting in the conference hall as she ponders to herself about Y/N.
Christina: ("I swear... I'll find Y/N and when I do... I'll kill him... for Darius... my parents... for everything he's done.")