Asks Kara to come into the training room

"Supergirl!" Alex yells, a few moments later, the girl of steel comes flying back in, looking a bit sheepish.
Pointing towards one of the hallways, Alex says "Let's go to the training room, I want to know what the hell you've gotten yourself into now."

Following along behind Alex, Kara pulls out a folded up paper from her golden belt "Um, well, I sort of went in a bit... recklessly? Trying to save some women that were caged up practically naked... turns out it was a sex club and they wanted to be there... and Roulette runs it. So... uh... I have to join her new fight club, and fight some fights at their level... and can you please say something Alex? This silence is killing me!"

Reaching a door, Alex types in her code and submits to a retinal scan, then points inside "Get in, and give me that" snatching the list from Kara's hand as she enters.

"So, I figure as I even beat you at times now, I should be-"

"What the fuck Kara? It says here both combatants have to be limited to the power level of the weakest of them, are you planning to fight Superman or does Roulette have Kryptonite?" the glare Alex gives Kara is a mix of fury and disappointment.

Turning away to avoid the look, Kara explains "I... I'm sorry Alex, and I sort of maybe... kinda... have a bracelet with some Kryptonite I got from the Fortress.... and some I... borrowed? From the DEO. It'll bring me down to human normal in power, though tougher!"

"Don't look so cheerful Kara, that you're tougher just means they can pummel you longer before you get knocked out" turning towards the door, Alex hits the button to lock the door and activate the Kryptonite emitters, turning the dial up a bit before facing Kara again "Now, let's see how well you do in a more even fight." before she starts moving, she presses her thumb against a small drawer under the control panel, and palms something from it as it pops open, putting it in her pocket.

"Uh, what, you want to spar now? And hey, that kinda hurts, you've got it turned up too high, I'm weaker than you now!" Kara starts backing up as Alex keeps advancing on her.

"Yes, you don't know your opponents, you don't know their powers, you don't know if Roulette will tell the truth, we both know she's a cheating bitch and she hates you. So I'm going to whoop your ass, then put you in a cell for 48 hours until after this ridiculous fight club is over, then we'll go deal with Roulette" Alex's steady pace increases as she talks and she's now almost jogging as Kara is increasingly scrabbling to stay away.

"No, you can't do that, she'll sue me, and ruin Supergirl's reputation, you-hey!" a moments distraction as she backs up and Alex lounges for her, almost but not quite managing to get a hold on her arm.

"Well I'm not gonna fight you, ok, we're going to talk about this like adults, and then leave and-hey, let go! That hurts you-ohmf" walking up to the stationary Supergirl, Alex grabs her right hand and twists it behind her back, swiping her legs from under her as she pushes the blonde to the ground.

"You're right, I didn't really want to fight you, so I'm glad you chose to stand there" taking the Kryptonite enhanced handcuffs from her pocket, Alex cuffs the hand she has, and then grabs the other forcing it behind Kara's back and into the handcuffs.

"Wha... you're cuffing me? With Kryptonite cuffs under Kryptonite emitters, you know how much it hurts when it gets this much! Please Alex" Kara's breathing is getting labored as the cumulative radiation is starting to have an effect.

Standing up and pulling a woozy Kara up as well, Alex hurries towards the door and hits the abort button, turning off both the emitters and the door lock.
"I'm sorry Kara, I really am, but you were reckless earlier tonight and extremely so making deals with Roulette and planning to de-power yourself, I can't just let you run of half cocked like that, the city needs Supergirl... and I don't want anything to happen to my sister, ok?" Opening the door, she starts to push Kara along towards the cells.

"Do you have any idea how patronizing you're being right now... I'm not just some symbol at the citys beck and call, I'm also not some helpless kid Alex, I'm an adult and your sister, can't we talk about this and figure it out? Instead of this... this power trip you're on? Protecting me by taking away my choices isn't protecting it's... wait... you're actually putting me in a cell? You can't do that! I didn't do anything illegal, wait, no Alex!" Kara's shouts become muffled as Alex pushes her into one of the empty cells and closes the door.
The cells being made of a transparent but close to indestructible material does nothing to hide from Alex the view of her sister sliding down along the wall until she's sitting crouched and despondent in a corner.
Pressing a call button on the cell wall, Alex glances over at the curiously watching prisoners in the other cells before she speaks into a microphone "I'm sorry... Supergirl, this really is for the best. Since we removed the emitters from the cells after the debacle with General Lane, you'll have to keep the cuffs... I'm truly sorry." waiting a minute for a reply that never comes, Alex shakes her head and walks back up to the command floor "Time to find out what Roulette is really up to."

In the cell, a softly crying Kara hears a light knocking on the wall next to her head "Hey... SG... sorry to see you with us. I know you helped put me in here, but I was drunk and eating someones car so I get it... You don't deserve to be thrown in here though, it's just the humans hating on aliens again, doesn't matter how much we do, they never really see us as their equals.
Once you get out of here, you should look up this support group I was in, Proud Aliens... they... they help you make sense of things, and find others suffering so we can come together, there is strength in numbers."

A sniffing Kara mumbles "El Mayarah."

Translated from Kryptonian:
El Mayarah - Stronger together (Motto of the house of El)