based on their little moment in episdoe 22 :3
Ryuko's heart beat a mile a minute. The final battle as about to begin. Her and Satsuki were on the same side now, fighting as one. It almost made her giddy with excitement. Of course, she would never tell the former student council president that. She looked over at Satsuki, and saw that her face was as serious as ever. "Aren't you going?" The older girl asked, in an almost reprimanding tone.
"What about you?" Ryuko responded. She didn't want to have to do this alone. Not after they bonded and called a truce.
Satsuki turned to her in almost disbelief. "I have no choice but to go." That insane monster coming towards them was her mother too. She couldn't just let Ryuko fight Ragyo on her own.
Ryuko snorted, walking past her sister. "Then hurry up and change." She dismissed.
A little later, after Satsuki had changed, the two sisters stood side by side, preparing themselves for what was to come. Neither of them knew, and the anxiousness of it all made Satsuki's stomach turn. This was it. This was the beginning final showdown. Standing here with her long lost sister, she didn't know if she should cry or laugh. But, she must keep her composer. For her Devas. For Ryuko.
Someone buzzed in on the earpiece in Ryuko's ear. "Lady Ryuko." It was Soroi. "Please take care of your sister." Such a simple command, yet it made the young girl blush. It sounded like something a doting mother would tell her oldest daughter before she'd let them both go play. A fantasy in her mind of Ragyo being a kind mother standing on the porch steps of a cottage house waving as she watched her two dear children go out to explore the world flashed briefly before she was momentarily queasy. Ragyo? A caring mother? Yeah right. "Gottcha."
She responded. She nodded at Satsuki. Her heart fluttered, wanting to try something she had been contemplating saying all day. "L-Let's go. Si-Si-" Dammit. sShe was stuttering. She took a quick breath. "Si-Si-" The word felt so familiar yet so foreign on her tongue. She wanted to say it, but she just couldn't. She was glad finally Satsuki stepped in to end her misery.
The older girl smiled a bit at her cute shyness. "You don't have to force yourself to act like my sister. Your blood flows through Junketsu right now. And that's enough for me." She appreciated Ryuko's effort, but it was clear they hadn't reached that point yet. Their relationship didn't have to start off on the sister page. They could become friends and work their way there. Satsuki was patient. Ryuko was unsure. The sister thing was new to the both of them. It was going to take some getting used to. Satsuki was just happy to have her sister back.
Ryuko looked up at her in bewilderment. The blush that had appeared never left her features. "That so?" Ryuko's life fiber heart pounded so much she could hear it in her ears.
"Yeah." Satsuki assured her proudly. Although she would never admit it to the younger girl's face, Satsuki wouldn't have anyone else as her sister.
"You girls…" Senketsu croaked, tearing up and enjoying the little, but very sentimental moment between the two young women. Ryuko couldn't help but smile at him. He was such a blubbering dork sometimes.
"Save the waterworks for later." She told him. Then she became serious. "Alright, let's do this!"
Satsuki took a deep, calming breath and both girls synchronized with their kamuis, flying off into battle with their hearts at ease.