https://tvtropes.org/pmwiki/pmwiki.php/Main/ArchEnemy
-The beginning of the story immediately sets Suko Chifumi up to be this for Chidori Chinatsu. A friendly restaurant owner who was revealed to be a ruthless serial killer and became a broken pedastal for Chidori that she had to tear down herself. Suko even swears vengeance on Chidori, promising to come back and make her life a living hell, while Chidori promises to be ready for her if she ever comes back only cements it.
https://tvtropes.org/pmwiki/pmwiki.php/ … lMeetAgain
-Suko, even on the verge of defeat, promises to return and swears vengeance on Chidori, promising to come back and torture and kill everyone she loves. Chidori's response is downright scathing.
https://tvtropes.org/pmwiki/pmwiki.php/ … SuckSpeech
-Chidori has a downright scathing swear word filled one ready for Suko after she swears vengeance. BEHOLD!
"BLOW IT OUT YOUR ASS, BITCH! Scream and cry and throw your little fucking tantrums all you want! You will NEVER destroy who I am! You're going to prison and you are going to rot away for the rest of your fucking life! Knowing that every god forsaken breath you take from this moment onward is a gift from me! I want you remember that, Chifumi! I want you to remember my hands on your throat! I want you to remember the fucking highschool girl you beat you! You remember that you psycho! You were brought down by a damn kid! I BEAT YOU! I BROKE YOU AND I DID IT WITHOUT STOOPING TO YOUR LEVEL! You've lost sicko. You've lost and you have the rest of your miserable life to reflect on that. Fuck it! Go ahead and tell everyone that I'm the Masked Schoolgirl. That you were beaten by a kid. It'll be blood in the water. Everyone will know what a pathetic little waste you really are then. Even if, by some fucking sadistic twist of fate you come back? There'll be blood in the water. You'll have nowhere to go. No one to turn to. Nobody to help you and enemies all around you. All of us will be waiting for you. I will be waiting for you. Pull whatever dirty underhanded tricks you want. You will never win, do you hear me?! I will always be here to stop you! Every fucking time. You will never break me, you got that, shithead? You will never win! Justice is served."
The best part is that Suko is basically left sputtering out a response and can only pathetically call out her name as Chidori walks away from her.
https://tvtropes.org/pmwiki/pmwiki.php/ … edBeatdown
-While we only saw the tail end of their fight, and it was still very violent, it ends with Suko being on the receiving end of one of these from Chidori. After unleashing a downright brutal multi-hit combo of martial arts moves on her and a further beating on top of it, Chidori ultimately knocks her to the ground, leaps on her and starts violently unloading on her to reduce Suko's face to a bloody mess and even starts strangling her to death! It's very clear that if Chidori hadn't pulled herself back from the abyss she would've strangled Suko to death right there. Suko is still tough enough to stab her and talk trash afterword though despite being completely wasted. It should be noted that Chidori was hitting Suko hard enough to break bones during this assault!
https://tvtropes.org/pmwiki/pmwiki.php/ … ppableRage
-A downplayed example but Chidori can be downright terrifying when she's pissed.
https://tvtropes.org/pmwiki/pmwiki.php/ … ryCollapse
-Chidori collapses from her wounds shortly after defeating Suko. Fortunately for her Hiro found her and took her to her home to heal. Which is extremely luck for Chidori, as she likely would've died from her wounds otherwise.
https://tvtropes.org/pmwiki/pmwiki.php/Main/DeepSleep
-Chidori is out of action for at least a day after the fight and wakes up covered in bandages hearing Hiro singing while tending to her.
https://tvtropes.org/pmwiki/pmwiki.php/ … YourHatred
-For reasons likely known only to her, Suko goads Chidori into killing her at the tail end of their fight when Chidori is standing over her with the bloody knife. The scary part? Chidori actually appears to be considering it before she snaps herself out of it.
https://tvtropes.org/pmwiki/pmwiki.php/ … eInTheDark
-At the end of the fight, Chidori has a chance to take the knife Suko used to stab her and turn it on her and give her what she deserves but chooses not to. Refusing to be anything like her, she throws the knife away.
https://tvtropes.org/pmwiki/pmwiki.php/ … ticOutcome
-Suko was a popular socialite who owned a popular local restaurant, so it's no surprise that her employees are being questioned by the police in the aftermath.
--Chidori might have won but facing off with a former friend who was revealed to be a serial killer is not going to leave you in a good place. Chidori is left bed ridden after the fight, albeit healing quickly, and breaks down crying while hugging Hiro.