(laughter is contagious)
Chekov wants to be treated like an adult. He really does. He can't help it if some of his more child-like tendencies seem to come out when he gets excited or when he gets sad. (He hops when he is excited, or taps his foot, his eyes gleam, sometimes, too—when he is sad, he just cries, and he cannot help it that he chokes, and moans, and—well, he is just an ugly crier, okay?)
Sometimes, at the console, Sulu will look at him with one eyebrow raised, and he will say, mostly serious, "Have you disengaged the external dampener?" or something particularly similar to what Spock said to Mr. Sulu on that day and Pavel will just explode with laughter. Squeaky, breathy, laughter that everyone will perk their heads up at upon hearing it; some will even laugh, too, or some will just look at Kirk in his chair, while he stares at Chekov.
When Chekov is laughing too hard, he will turn around to check if he is making a scene, and most of the time (99.99 percent of the time, actually), he will see Kirk or a lot of the bridge crew just looking at him.
When this happens, Chekov will either (a) play it off, or (b) apologize profusely and blush like a beet in a bowl of borscht, and remain embarrassed for the rest of his shift and curse Sulu for being so damn funny.
On this particular day, he went with option (c), which, extraordinarily, has never been put in effect before today.
"Chekov," Sulu said, turning in his seat, and looking at Chekov with that cocked-eyebrow look and Chekov was already giggling.
"Swiggity swag, what's in the—" And before Sulu could even finish his sentence, Chekov absolutely lost it, turning around in his seat and doubling over to laugh even harder.
Pavel squeaked, and a loud metallic thud sounded, an indicator that he had fallen off of his seat. Yet, surprisingly, Pavel had not ceased his hysterical laughter.
Kirk had no idea what to do other than watch amusedly and say, "Well, shit, Sulu. You broke him."
Sulu's eyes darted to Chekov (still laughing, of course), then to Kirk, panicked, "Sorry, sir, I just. . ." he trailed off, simply reevaluating his entire life and wondering whether he really was funny or not and whether he should use this talent for good or evil.
After a few moments of Kirk and Sulu and eventually Spock going back and forth ("Captain—"
"Sulu, please just never tell him a joke while he's on his shift ever again—"
"I wasn't aware that 'joke-telling' was permitted while on duty." "Spock!"), Chekov finally stopped laughing, and went limp on the floor next to his chair.
"Fuckin'—call McCoy!" Kirk threw his hands up, "I will not have anyone on my ship die of laughter!" he added, trying very desperately to keep his own chuckle in.
Pavel came around some few minutes later in the Med-Bay, blinking and looking around. He recognized where he was immediately, and rubbed his eyes, sitting up. Reaching an arm up to run a hand through his curls, he found that he had an IV in the crook of his arm.
"Slow down, tiger,"
Chekov looked up to see McCoy typing something in his PADD, and eased himself back down, sighing.
"You passed out on the bridge. Can't say I've ever seen anyone get put in sick bay for laughing their ass off to the point where they cut off their own oxygen supply."
"So Spock and I carried you up here, and I come to find out that you are dehydrated. Hence the IV," McCoy explains. He turns the PADD around to shoe Chekov what he's looking at, which so happens to be—
—Chekov's replicator record. Everything that Pavel has ever requested from the replicator, displayed on a spreadsheet for the good doctor to analyze. Pavel assumed that Dr. McCoy could only access it because he was CMO. But Pavel wondered why he even wanted to access it anyway, what was the point?
"Chekov," the southerner starts, highlighting a specific section on his record, "can you tell me why you are drinking nothing but chocolate milk and apple juice?"
the Russian looked guilty for a long minute, his gaze remaining downward for a while.
"Chekov, look at me, now. I don't want to treat you like a child."
Finally, Pavel looked up. "Is delicious. . .?" He sighed.
McCoy shook his head, slightly disappointed. "Listen, Pavel,"
Oh, goodness. Pavel already knew this wasn't going to end well.
"You need to stay hydrated and drink water. Alright, kiddo? Next time I see red in your replicator record," McCoy tapped the PADD for emphasis, "I'll do something about it."
"Good boy. Now finish off this bag and you can go. Kirk gave you the rest of the day off, the bastard— have some fun. Have some water, too, so you don't puke up your stomach." McCoy said, tapping the IV bladder and walking away to some other poor dehydrated crew member.
Chekov sighed again, covering his face with his free arm. Again, McCoy treating him like a child—a part of him was angered by this but he also knew in the back of his head that he deserved this treatment.
He was still a lost child, seventeen years old—immature, irresponsible, and coincidentally, with a lot under his belt.
Today, Pavel Chekov vowed to be even more mature than he already was.