Just the start of something between Kai and Mao, taking into account Mao's character arc and the fact that they're sisters. Posting what I have now because it's getting late and I should be getting some sleep soon (psh, like I ever sleep when I say I will, but whatever...) so here's something for your consideration?
The abandoned warehouse where Kai sat echoed with the sounds of battle as a lone Tumblranger fought through wave after wave of Fujoshitappa. The Feels Minister sipped her tea calmly even as the last of her small army was blasted through a wall to her left; without blinking, she brushed some dirt from the small tea table that she was sitting at and readjusted the china disturbed by the sonic attack. Only when the approaching footsteps came to a halt just in front of her did she look up from her phone, smiling at the weapon pointed at her face.
"Mao-chan!" With one finger, she moved the megaphone out of her line of sight in order to look TumblrYellow in the face. "You got here faster than I expected! I'm impressed."
"Where are the other Tumblrangers?" The megaphone was back in Kai's face a moment later, but the minister had resumed sipping her tea carelessly. "I didn't come here to play games with you, Kai!"
"It's been so long since we really talked, sister." Kai gestured at the other chair and the teapot and mug in front of it. "I even made your favorite tea, just like you like it. Come and talk for a bit. Your friends are perfectly fine."
The megaphone wavered as TumblrYellow glanced at the teapot. "I want to see my friends first."
With a sigh, Kai showed her the screen of her KaiPhone. A live feed showed the other Tumblrangers in a cell, untransformed and handcuffed but obviously unharmed. After studying the screen for a second, Mao nodded, undoing her own transformation and sitting carefully in the other chair.
"So." Kai reached over to pour her sister a cup of tea, then returned to sipping her own. "This is the point where I offer you a choice. Ah-ah--" she interrupted herself when Mao started to speak. "Listen carefully. You'll want to choose carefully here. On the one hand, your friends. If you pick them, I'll let you attempt to rescue them. You've beaten up enough of my Fujoshitappa that you should be able to get them out of their cell. I won't stop you." Mao raised a skeptical eyebrow, and she chuckled. "But your other choice is to have all your wildest dreams realized. I can make you an idol and a celebrated hero, Mao-chan -- all you have to do is leave the Tumblrangers with me."