This one is inspired by that one moment during the Three Kings arc where Mukoro is Calling Hiei On His Shit, as she does, and asks if he's serious about the whole "grr I don't care about people, I will fight anyone, just watch me" thing and then the camera pans directly to Kurama and Mukuro is Very Pointedly looking at him like "Really, Hiei? You're gonna fight your crush, too?" and he misunderstands and says "yeah, I'll even fight you". Like, let's not forget, Hiei, in like episode 10 you said the only reason you became his partner (besides the crush thing, the crush thing is very real and you can fight me on that) was to avoid fighting him yourself so i'm calling bullshit on that one

So

Just

Yeah

"Bullshit," Mukuro said, not looking away from her work on the machine above her head. Something had backfired within the depths of the giant insect, causing the entire fortress to halt in its progress toward Raizen's old territory. She didn't trust the engineers to fix the cataclysmic error, and several had been succinctly disposed of in the aftermath of the malfunction. Currently, she lay on her back, squeezed underneath a massive contraption, rooting around among gears and wires, swearing and banging on metal with a variety of tools for which Hiei had no name. She was covered in grease, though only the lower section of her legs were visible to anyone standing by.

Hiei leaned casually against the metal wall to the left of the contraption, looking over the machinery with mild interest. In his time at her fortress, he'd learned a fair amount about the technology Mukuro had at her disposal, but the intricacies of the inner mechanics of the bug itself were still somewhat lost on him. He made a mental note to spend some time in the belly of the keep. Constant improvement and all that.

Mukuro aimed a swift kick at Hiei's shin, tearing him from his thoughts. He aimed a glare at where her head would be, bristling slightly at the fact that it actually hurt.

"If you're going to hang out here while you mope, you might as well make yourself useful. Hand me that wrench."

Hiei, ever ornery, rolled his eyes as he bent to retrieve the tool.

"He's become complacent. He'll rot in that human shell until he can't even defend that precious mother of his," his voice dripped with disdain and frustration.

Mukuro grabbed the wrench from his outstretched hand and rolled her eyes as well. "You may be a prodigy by most standards, but never forget that that fox has been a deadly legend for longer than you've been alive. I won't pretend to understand his current situation, but I'm certainly not stupid enough to think he's any less of a threat now than he ever was at the height of his power."

Hiei wasn't exactly sure how to process the statement, which, in spite of its derogatory tone, still held a complement.

"I know that." he spat. Lashing out was really his only way of dealing with such things. "But there are plenty of demons who don't, ones who would challenge him if they think he's weak."

Mukuro smirked up at the washer she was tightening. "Then they will soon learn. You still didn't answer my question. Why are you so concerned about whether or not he participates in the tournament?"

"Because he's a demon!" He snapped, voice pinging off the metal and distorting his tone. "He should want to fight! He should want to show the world just how deadly Youko Kurama is-in any form!"

"Apparently he does not share the sentiment," Mukuro replied cheerfully (or as cheerfully as Mukuro could ever reply). "If he's not concerned about his reputation, I fail to see why you're so worked up about it."

"I am not 'worked up'," Hiei huffed, crossing his arms petulantly.

Mukuro said nothing.

Hiei fidgeted, ill-contained and aggravated. "It's a shame. To see a demon of such...magnitude-"

"Oh please, do regale me with another one of your infatuated speeches about the great Youko Kurama," Mukuro laughed without humor. "There's nothing I enjoy more than listening to you go on and on about the magnificent, deadly-"

She was interrupted by a loud clang as some tool of hers was flung at the pipe above her head.

"I am not infatuated," Hiei sneered. He was angry, she could tell, far past the point of good humor and edging into a dark and dangerous version of Hiei. One that occasionally let loose a fiery dragon to run rampant and destroy everything in sight.

A lesser demon may have backed down at the notion, but if Mukuro enjoyed anything about her life, pissing off Hiei was probably one of her top three favorite pastimes.

Mukuro slid out from under the machine, and looked up at Hiei with a composed, if slightly amused, expression.

"Bullshit," she repeated.

She rose to her feet and wiped some of the grease from her hands onto her pants.

"You absolutely are infatuated and don't you dare try to deny it. You don't want Kurama to come to the tournament so he can prove something, you just want to see him in action." She shouldered past him, towards the door, turning her head slightly to look at him with a curious expression. "I wonder what would happen if fate pitted the two of you against each other."

"I'll fight anyone who challenges me," Hiei growled, teeth and fists clenched. "You know that."

Mukuro began out the door. "And yet, he's not challenging you. Poor, Hiei, all this pent up tension, and no where to go…"

The door swung shut behind her, leaving Hiei alone among the machines.

Mukuro and Yomi probably have lunch every once in awhile just to laugh about how f*cking stupid their seconds are. Maybe I'll write that as a companion piece.

For more of these two being teased mercilessly by their employers, I'm going to plug "con·tra·dic·tion" by caseyvalhalla because it's a hilarious and very well written piece.