Disclaimer: I do not own Teenage Mutant Ninja Turtles. Rated T for language.

A is for Asshole

And here Donatello had thought that the training session couldn't get any worse.

He knew intrinsically that it was his own fault, at least partially. He was well aware that a good night's rest was important for the development of 11-year-old minds, and the rabbit hole of research he'd been down on his computer last night had left little time for such menial things as sleep. After all, there were so few hours in a day but so many essays, forums, and videos about how to build your own internal combustion engine. So he couldn't say he was surprised when his energy started fading drastically when they were only about halfway through training, which was not at all helpful when it came to learning the precise movements of the new kata Sensei had decided to teach them.

His sluggish reactions earned him constant correction from his father and snickers from his brothers, only flustering him more. And now he stood face-to-face with the one brother he would have given anything to avoid in such a situation.

"Think you can stay on your feet long enough to let me get some real practice in?"

The smirk on Raphael's face was so smug that Donatello wanted nothing more than to kick it off. His face set with a determined frown, Donnie waited in his stance for Raph to make the first practiced move. With a loud grunt, his older brother finally threw the first punch for him to block using their new kata and then another before Donnie finished with a kick towards his abdomen. Raph was supposed to roll backwards to absorb the blow, but instead he stood firm, his grin widening.

"That was it? Pretty sure Spike could've hit me harder than that."

"It's about building muscle memory, you meathead," huffed Donnie as he returned to his opening stance.

His brother's eyes narrowed at the insult, but the edges of his mouth remained crooked upwards as he too took his proper position before repeating the instigating moves of the kata. With both punches blocked, Donnie set his jaw and kicked his leg out with all the force his tired body could muster, causing Raph—who was once again stubbornly standing his ground—to grunt. Donnie noticed the dangerous gleam in his eye a fraction of a second too late, however, as his brother suddenly broke form, reaching out to grab his leg and jerk it roughly. With a startled cry, he hit the ground with a dull thud, the unexpected impact knocking the wind out of him.

"I dunno," said Raph with a snicker, "I think my way works just fine." He reached out a hand to help his sibling to his feet, but Donnie growled and smacked it away.

"Damn it, Raph! Why do you have to be such an asshole!?"

The instant the words rang throughout the room, he clamped his mouth shut tight, his brown eyes widening to match the green ones staring back at him in shock. Quiet gasps from their uninvolved siblings reached Donnie's ears as time seemed to pause, his brain scrambling to find a way to undo his verbal blunder before at last Leonardo's voice broke through his tangled web of thoughts.

"You know you shouldn't talk like that, Donnie!"

"Sensei, what's an 'ass—'"

"Donatello," Master Splinter's firm but calm voice cut off Michelangelo before he could finish his question, "where exactly did you learn such language?"

Quickly facing his sensei and righting himself into a proper seiza position, Donnie's eyes flicked up to the imposing figure and back down to the knees he knelt upon. "Well, um, I don't know that I can say exactly where I learned it, Sensei. I mean, well, the humans that frequent the online forums I use for research can be pretty disrespectful when there's a disagreement over the proper solution to a presented problem." His voice grew less timid as he carefully sifted through his mental notes, raising a hand to his chin in thought, "But then again, some of the hosts of the videos can be pretty crass at times, often using varied and colorful language to emphasize—"

A sharp tap from Splinter's walking stick striking the floor silenced Donnie's rambling instantly, causing him to flinch as he was quickly reminded of his current predicament. Upon hearing a coughing noise that sounded suspiciously like the word "nerd", he shot Raphael a sharp glare before returning his eyes sheepishly to his father from where he knelt.

"So," said Splinter, keeping his voice quiet but authoritative as he stroked his long, thin beard, "you learned them through your computer. Is that correct?"

Donatello nodded with a mumbled, "Hai, Sensei."

Closing his eyes, Splinter gave a soft sigh and nodded before returning his gaze to the son that knelt before him. "You know such language is unacceptable, especially when directed at one of your brothers."

"But Sensei—"

"Words amongst family should be used to build one another up, not tear each other down. None of you should be quick to provoke anger or call your brothers disrespectful names, whether it be one of your unsavory new words or even something as simple as 'nerd'. " His attention shifted toward Raph whose quiet snickering came to an abrupt halt as all eyes followed their sensei's gaze, "Isn't that right, Raphael?"

Raph merely pouted and muttered a soft, "Hai, Sensei."

Focusing again on the younger of the two, Splinter continued, "Donatello, when we are finished training, you and Raphael will work together to clean the kitchen—"

Raph's head shot up at the sound of his name. "Wait, why do I—!?"

"Do not think I did not catch your improvisation of the kako no kata," their sensei said sharply. Clasping both hands on top of his walking stick, he glanced back and forth between his obstinate sons, his posture alone enough to command their attention. "If the two of you have not yet managed to show proper teamwork by the time you have finished with the kitchen, you will continue to other areas until you do. Do I make myself clear?"

Both brothers shot a disgruntled glare at each other before replying in resigned unison, "Hai, Sensei."

Splinter relaxed his stance and again softened his tone, "Good. Now, Donatello, once you are finished, I want you to bring your computer to me. You will teach me how you use it. I wish to see for myself these forums and videos you spoke of." Donnie nodded glumly in response, but his father wasn't finished. "You will then leave it with me for the next three days so I may familiarize myself with how it works."

Donnie's jaw dropped. "Three days!? But—"

"Would you prefer I borrow it for a week?"

Shoulders slumping forward, he sighed and answered, "No..." as he pushed himself back onto his feet.

"I know you have built a powerful and useful tool, Donatello," Splinter said, reaching out a hand and placing it on his dejected son's shoulder as Donnie looked up forlornly to meet his father's gaze. "But considering the influence it has had over not only your words but your ability to appropriately manage your sleeping habits, I think some time apart from it would not do you any harm."

The incredulous look on the young turtle's face voiced his opinion without words. With a knowing smile born of age and experience, Master Splinter gave his shoulder a light squeeze before moving back toward the center of the dojo.

"Now, all of you, back into position. It is not yet time for a rest, Michelangelo."

As Mikey jumped up to rejoin Leo from where he'd sprawled out on the floor, training resumed as if it had never been interrupted. Raph huffed as he begrudgingly rolled backwards after Donnie's kicks, performing his part as instructed. Donnie feared that his brother might use a bit more force than necessary when it came time for them to switch places, but, while Raph's kicks weren't exactly light, he seemed to be taking the exercise seriously. Having fully expected him to take out his anger over his punishment on the practically gift-wrapped, turtle-shaped punching bag before him, Donnie instead began to wonder if his older brother was biding his time, waiting to strike until they were alone in the kitchen with no witnesses.

As soon as training had finished, their father had made sure the two disruptive boys headed straight for the kitchen to begin their assigned task. Dirty dishes from breakfast sat on the stove and in the sink, while the counter, makeshift island, and floor were littered with crumbs, spots of water, and the occasional dirty napkin. With a sigh, Donatello opened the cabinet under the sink and pulled out the soap, some rags, and a drying rack. Placing the rack next to the sink, he plugged up the bottom and turned on the water.

Grabbing one of the towels hanging on the handle of the oven's door, he tossed it to Raph. "I'll wash and rinse. You dry and put them away." A short "hmph" was the only response he got, but as Donnie added the rest of the dirty dishes to the sudsy water, his brother shuffled up beside him, arms crossed stubbornly but towel in hand.

The two stood in relative silence, the only noise coming from the splashing water or clinking of plates and cookware as Donnie filled the drying rack. Every time Raph would reach for another dish to dry, Donnie tensed ever so slightly, wondering what form of revenge his brother must be plotting to keep him so quiet when usually he'd be loudly complaining about the injustice of it all. So when Raph did at last speak up, Donnie braced for the worst.

"So what'd that mean, anyway?"

His hands pausing mid-scrub, Donatello was caught off guard by the seemingly innocuous question. He turned to his brother and blinked. "Huh?"

Raphael cocked an eyeridge at him as he picked up a wet plate. "You know, what you called me? That word that got us into this whole mess?"

Donnie's eyes narrowed as he frowned and said, "You got yourself 'into this whole mess', Raph. And it means 'someone who is intentionally callous, belligerent, and arrogant'."

Raph stopped rubbing the plate with his towel and gave his brother a flat look. "In English?"

"'You're—a—big—jerk'," explained Donnie in a slow, even tone as he rinsed the pan he had been washing and shoved it roughly into the drying rack.

There was a pause as Raph stared at him curiously before blurting out, "That's it?"

"It is a particularly crass way of saying it, but yes. That's it," he answered, eyes trained on the culinary knives in his hands.

The sounds of the dishes being washed and put away filled the room once again as the conversation petered out. Donatello kept his focus on his task, perfectly content to sustain the silence that emanated from the two siblings. Soon every dirty dish had been washed and rinsed, and he reached into the now tainted water and pulled the plug, allowing it to swirl down the drain and out into the sewers beyond. As his brother passed behind him with some clean cups to put away, he grabbed a towel to dry his hands so he could move on to his next task.

"Sorry."

Donnie jumped despite the quiet tone and looked up in surprise. "What?"

Raph hopped up onto the counter to reach the cupboard that held their drinkware, pulling it open as he said, "I was just messin' around. But I musta really made you mad for you to say that in front of Splinter. So," with the cups put away, he closed the door and landed back on the floor with a light thump, his green eyes finally meeting brown, "sorry."

Staring at his brother in shock, all Donnie could think to say was, "Oh."

After a rather pregnant pause, Raph huffed and pushed past his bewildered sibling to grab the last items in the drying rack. Donnie finally flinched when one of the knives he'd washed earlier was pointed in his direction.

"Don't just stand there," said Raph as he brandished the utensil toward Donnie, sending droplets of water flying before wiping it dry. "Let's hurry up and get this over with."

"Right," said Donnie as he shook his head as if dispelling a dream. Replacing the towel, he picked up a dry rag, grabbed the trash can, and began wiping the crumbs and trash on the island into it. As he worked, he found his mood brightening, the tense atmosphere from earlier completely dissipated. His grumpiest sibling rarely apologized, but when he did, he meant it. It almost made Donatello feel bad for using such harsh language against him in the first place. Almost.

The two continued to wipe and scrub the island, counters, stove, and sink until all that remained was the floor. Handing Raph the dustpan, Donnie began sweeping the accumulated filth into it, and this time when his older brother's voice broke the now amiable silence, he listened without apprehension.

"So," Raph began casually, "'asspull', right?"

Donatello spoke automatically, "It's 'ass—'" His self-preservation suddenly kicking in, he quickly glanced at the kitchen entrance before lowering his voice, "It's 'asshole'. And I shouldn't have called you that, so don't you start saying it either."

"Just tryin'a be as smart as you, Donnie, " he said with a smirk as he glanced up from where he was crouched on the floor.

With a goading smile of his own, Donnie rolled his eyes as he swept more dirt onto the dustpan and said, "In your dreams."

"So what other bad words do you know?" Raph asked as he got up to toss the collected dirt and waste into the trash.

"Even if I did know more 'bad words', I wouldn't tell you," replied Donnie as he continued his sweeping. "Sensei would know who you learned them from, and then I'd get in trouble, too."

"I'm not stupid enough to use them around Master Splinter," said Raph with a grin. As his younger brother snorted and shot him a disbelieving glance, he walked up beside him, leaning against the island with his arms folded, dustpan hanging limp and forgotten. "Come on, you've gotta know something better than a fancy way of saying 'jerk'."

At this, Donnie paused and held up a finger. "Well, the technical definition is another name for one's anus, as 'ass' is a slang term for 'butt', ergo, 'butthole'. That doesn't appear to be a very common usage of the term, however."

Raph snickered and raised an eyeridge. "You called me a butthole? What, is calling somebody a 'mouthhole' an insult, too?"

With another roll of his eyes, Donnie resumed his sweeping as he spoke, "No. Although, come to think of it, there are several curse words that are related to the butt in some way. Synonyms for urinating, defecating, and even male genitalia all seem to be in fairly common use." A fresh pile of dirt ready and waiting, he glanced expectantly at his brother who now had a devious gleam in his eyes.

"Really," said Raph as he once again bent down and lowered the dustpan to the floor, "and what words are those?"

"Nice try, Raph."

"Hmph," replied the older turtle with a pout as his dustpan once again received the latest harvest of loose dirt and crumbs.

As Donatello watched Raphael plod back to the garbage can, a sudden thought occurred to him. Bringing his hand up to his chin, the corners of his mouth quirked downwards in contemplation as a particular word bounced around the confines of his brain.

"You know," he began slowly, instantly grabbing his older brother's attention, "there is one that technically can be used as just a normal word. It refers to a 'female dog', but it's an insult when directed at somebody. Oh, and you can use it as an expletive as well, like we would use the word 'darn' or 'heck', so it's especially versatile." The anticipation on Raph's face told Donnie that he had his full and undivided attention. With a grin, he continued, "In that case, it's used at the end of a phrase, so you couldn't just say the word by itself, you'd have to use the full expression: 'son of a—'"

A/N: Raph is an enabler, and Donnie absolutely knows the most curse words of the four. Also reminder that Hamato Yoshi was first mutated and driven underground in 1997, so at best he'd only ever had access to a slow and crappy dial up internet connection - guy is learning the hard way about what kind of chaos could be influencing his kids on that thing.

As always, critics and grammar police appreciated!