Author's Notes/Warnings: Written for a prompt at the KuroFai comm's "Headcanon Ficathon" that read, "Holitsuba!Kurogane is the first person who hasn't been jealous of Fai and Yuui's closeness." KuroFai, PG-13 for implied sex and general behavior utterly inappropriate for professionals in the workplace.

"Kuro-sama~ Do you have a minute?"

He rolled his eyes and then looked toward his office door. Usually it was Kuro-pyon or Kuro-puppy or whatever new mangling of his name the idiot hoped would get a good (read: bad) reaction. Fai using this particular nickname right out of the gate could only mean one thing; he was buttering Kurogane up in preparation for a request or an apology. Possibly a request that would later require an apology.

"Yuui's running a low-grade fever so I'm going to take him to the doctor's and then home," Fai announced, hop-skipping into the office and curling up neatly on a corner of his significant other's desk in a way that shouldn't have been possible for someone so long and lanky. "I don't want him to be alone tonight so I won't be able to make our date this evening."

"Good, because I never agreed to go on one with you," Kurogane replied flatly, tugging on a folder to try and retrieve it from under a bony butt. He made a mental note to check on the chef later, possibly with some cartons of soup from one of their favorite restaurants. Fai loved his little brother like nothing under the sun and would do anything for him, but all of the culinary talent had gone to Yuui when the twins had split in the womb. Kurogane didn't trust the idiot on his desk not to make his ailing brother even worse by force-feeding him some bizarre chicken chile cheese soup recipe he'd found on the internet.

"Kuro-cruel, how can you say that? Our burgers, beer and butt-sex mid-week break is such a long-standing tradition!"

The accusation and claim were filed in the To Be Ignored corner of his mind with a sigh, and then Kurogane flapped his rescued folder like he was trying to shoo away an irritating fly. Which, basically, he was.

"Next time just text me. I'm busy, and you have a brother to drive to the hospital."

"His appointment's not for another hour," Fai replied with a shrug. "He's taking a nap in the nurse's office right now." He slithered off of the desk, making a few papers slide dangerously close to the edge as he sashayed his way over to the door, and subsequently making the phys-ed instructor abandon his typing once more to lunge for the documents. It seemed the most natural thing in the world for Kurogane's eyes to cut quickly over to the papers in alarm and then move upward to those hips swaying directly beyond them, and when the swaying stopped Kurogane glanced up and bristled at the smug, knowing smile being thrown over one shoulder.

"What?" he growled, less a question and more a dare to answer. He added a quick glower and determinedly went back to typing up quarterly report cards.

"Welllll," Fai drawled, one hand settling on the lock to the door and the other hooking into a belt loop, making his jeans drag down so that a slash of skin, pale and perfect, showed below the hem of his black turtleneck. Not that Kurogane had let his eyes flicker over to check. "I wanted to make my apologies in person and see if perhaps a proactive beej might prevent feelings of disappointment and jealousy later."

Kurogane utterly blanked on how to spell "effort" as he let this offer sink in, then finally gave up on work and pushed his keyboard away.

"I have nightmares about the fact that you're entrusted with the minds of young people," he informed the chemistry teacher, sinking back into his chair and wiping one hand down his face in resignation.

"So should I lock the door?"

"You should shut it on the way out," Kurogane said flatly, firmly stomping on any thoughts of answering in the affirmative. Not that he wasn't tempted or was even too ethical to have sex on campus with a colleague during school hours. He had been more of a stickler for propriety at one point, but there were many winks and whispers and soft breaths raising gooseflesh on his skin gone by between then and now. So it wasn't disinterest or propriety that kept him from crowding Fai against the door so that he could lock it himself, but common sense and a bit of stubbornness.

Giving in to the blond's whims too often would make him absolutely insufferable. The surest way of keeping Fai manageably happy was to keep him reined in.

"You don't have to apologize for wanting to take care of your brother, idiot," he continued with a growl. "That's more important than grabbing a burger-"

"-or your butt?"

"Get out."

Fai remained by the door, now looking at him with a thoughtful little pout instead of a playful smirk.

"You're really not mad," the blond observed, his tone mildly surprised. "Not even a smidgen jealous. This has to be at least the third time this month I've thrown you over in favor of spending time with Yuui, and-"

"He's your brother," Kurogane interrupted.

"And you're my boyfriend."

"And we're both important to you, so what does it matter which one of us gets your attention at 7:00pm on Wednesday?" This question was put to Fai with almost enough exasperation to merit an exclamation point at the end, but then it became Kurogane's turn to look perplexed as Fai locked the door and began advancing on him in a way that reminded him of a big cat stalking something helpless and very, very tasty. The helpless tidbit was him in this case, but he couldn't really argue against the impression since the hip-slinky way the man walked across the room had Kurogane a bit weak in the knees, even sitting down.

He knew that look.

"I said," he began to argue, though with a bit less ire in his voice than a moment earlier. It was difficult to growl effectively when his mouth had gone suddenly dry and there was a very distracting ball of anticipation unraveling down his core and pooling hotly in his gut.

"I heard you," Fai purred, leaning in close, fingers tented on the suddenly speechless teacher's knees to steady himself as he knelt between them. "This isn't an apology. This is appreciation."

"For what?" Kurogane asked, after one faint croak and a hasty throat-clearing.

"For being you," Fai answered, leaning up and hauling him forward in his chair by the collar to give him a quick peck on the lips. "And for letting me be me," the blond added, a funny little crooked smile dancing about his lips as he settled back down. Kurogane reviewed this reply and found that it didn't make any sense at all, but by then his pants were open and Fai wasn't talking nonsense anymore, and the question became unimportant.