Rui sat filling out the last of the paperwork at headquarters, wondering where Katsuki was. It had been nearly an hour since the big fight and he still hadn't shown up.

'That moron... leaving me to do his paperwork again...'

Finishing with the final form, Rui stacked the paperwork neatly together and placed it into a folder before setting it on Gunhead's desk. Stretching, she made her way towards the dojo to get in some training- hoping that would help ease her mind. She began by walking herself through each of her own techniques, moving her water as she worked through each Tai'chi move she knew. After a half-hour, she then moved onto what Gunhead had taught her and was so focused on her training that she didn't notice that someone else had come into the training room. When she turned and kicked at what she thought was air, her calf connected with someone's forearm as they blocked her kick.

"Where have you been?" she asked, lowering her leg when she saw who it was.

"Busy," Katsuki replied, his eyes narrowed.

Rui narrowed her eyes slightly in return, then lowered her leg and stepped back. "Next time you decide to pull the disappearing act, I'm not doing your paperwork for you."

Katsuki watched her a moment as she turned away. "I didn't ask you to do anything for me."

Rui was getting annoyed and bent down to grab her water bottle. "Well someone needed to do it and you were 'busy'."

Katsuki rolled his eyes and pulled off his gauntlets, setting them down with his bag before stretching. "Whatever, I'm here now aren't I?"

Rui glanced at him from over her water bottle. "Better late than never, I suppose. At least you showed up for some training unless you still need some along time?"

"Let's just get this over with," Katsuki retorted and took his stance.

As Rui took hers, Gunhead had returned and spotted them getting ready to spar- standing just outside of the dojo to observe their match. Rui waited for him to make a move, curious to see how their little sparring match would go since they had never faced each other before. Katsuki knew she was waiting for him, so he made the first move and lunged at her. Rui was quicker than him, but she wasn't as strong as he was physically- something he noticed hadn't changed as they moved quickly around each other.

Rui leaped back, landing in a low crouch, panting as she licked the blood coming from her lip.

"Not bad," Katsuki said, smirking, "but still not good enough to beat me."

Rui narrowed her eyes at Katsuki as he made the comment. "Don't patronize me," she said, then lunged at him and took the offensive.

As always, their punches and kicks were quick and Katsuki continued with a series of punches, smirking when the last broke her defense and grazed her side. Rui grunted but ignored the stinging in her side as she grabbed his outstretched arm and used his momentum against him. Slamming him into the ground, she pinned his arm against his back and leaned down next to his ear.

Katsuki felt that same strange sensation run through his body again as he felt the warmth of her breath on his ear and neck but being well-practiced in grappling, he was quick to overpower Rui and slipped out from underneath her with ease. Flipping her onto her back, he kept her trapped beneath him as he pinned her to the ground- smirking as she struggled to free herself. Rui was well practiced in this type of fighting style thanks to her combative training with Gunhead, but Katsuki was much stronger than her physically and she couldn't get free.

"Yield, Rui, this match is mine," Katsuki said, his soft puffs of breath warm against her neck and ear as he leaned closer.

A soft and low groan escaped her throat as Rui looked at him. "Like hell."

Katsuki shifted his weight and flexed his muscles in accordance with her struggling as a sense of renewed energy seemed to pop out of nowhere. "You're not going to win this."

Rui winced as he tightened his grip even further as she continued to struggle. Her cheeks burned as the feeling of his grip around her sent that strange sensation through her body- unsure how she felt about the growing familiarity of it. She huffed, trying to break free, but was only able to free her hands for a brief moment and she tried to push him away- beginning to get irritated with his taunting.

The moment he let go of her wrists to change his grip on her again, she forced herself from his grip and flipped backward- landing softly on her water board as she summoned it to cushion her landing. Summoning her water board threw Katsuki off, but she could see that he was getting fired up again at the sight of her challenge.

"Using our quirks, now, huh?" Katsuki chided sarcastically. His grin only grew, though, as he dropped into a low crouch and readied to launch himself at her.

Rui glared at him, but she met him nonetheless as he propelled himself towards her. She used the fluidity of her quirk to her advantage, swiftly moving out of his way and getting behind him. Catching him off guard, she fired a series of water balls at him and knocked him to the floor. As he slammed into the floor, she dropped down from her water board and pinned him beneath a blanket of heavy water.

"The match is mine, you've lost."

Katsuki glared up at her, feeling beyond irritated- especially seeing her look so smug. "Fine, whatever, you win..."

Rui smirked and let him up, releasing the water and letting it soak straight through to his skin. "Who's the sore loser now?" She turned and went over to her things, gathering them up before standing straight.

Katsuki pushed himself to his feet and turned towards her, marching over to where she stood with her things. When she turned around, she jumped at his close proximity. "Don't go thinking that you're better than me just because you won this time," he growled, his eyes narrowed.

Rui stood her ground, her smirk fading into a frown and a sigh. "I have never once thought I was better than you, Katsuki, and the fact that you would think I ever could, tells me that you're still as childish as always," she looked him up and down for a moment, then added, "even with as much as you've grown."

Before she could walk away, Katsuki reached up and grabbed her arm. "We're not done here, Rui,"

Rui glared at him and pulled her arm free. "Yes, we are."

Katsuki stood there, alone and left to muddle through his tirade of mixed emotions once again. "Damn it, damn it, damn it!" He turned and fired a blast at the nearest punching bag, lowering his fist and arm as it exploded. "Damn it..."