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Deep in the forest at the heart of the island he called home, Luffy looked around with a huff. Above him stretched trees as old as the forest itself, ancient trunks mottled with lichen, broad green leaves blotting out the sun in patches. Gnarled roots criss-crossed through the dirt below, weaving a natural obstacle course into the path. He’d set out that morning with Ace at his side and the promise of adventure ahead. But when he’d been distracted by the sight of an ultra-rare beetle, Ace had used the opportunity to slip away.
At first, Luffy had been excited. He was no stranger to this game: he had come to expect the smile Ace would give him just before disappearing, the one that said catch me if you can, and there were few things he relished more than the thrill of the chase. But that was hours ago, and while Luffy had tried his best to watch out for the signs Ace had left in his wake, it was hard to stay focused when he was getting so bored. At this rate, he was pretty sure this hike would last forever. The only thing carrying him at this point was the thought that this was supposed to be Ace’s going away party, and there was no way Luffy would stand him up.
“What kind of party only has two guests?” Luffy had said when Ace first proposed the idea. The parties he was used to were always packed wall to wall with friends and neighbors alike.
“The best kind,” Ace had said with his signature lopsided grin. “C’mon, don’t you want to see my secret spot?”
Luffy’s eyes had gone round as saucers. “The secret spot?”
Luffy had been trying to follow Ace to that spot for as long as Ace had been going there. Now, Ace was offering him a golden opportunity to see what all the fuss was about.
“That’s the one. Now are you in or not?”
Of course Luffy was in, but he should have known better than to think that Ace would just let him have it. This was a test, he knew, to see if he could be trusted with it once Ace went away. The spot would be passed down from one brother to another, but only if he could prove himself worthy of it.
The thought bolstered his resolve. He studied a smudged imprint of Ace’s shoe with renewed interest, at last catching sight of the next faint impression showing him which direction to go. As he followed it doggedly down the path, he thought he heard something in the distance. He cocked his head. It was a sort of growling sound, but it wasn’t the growl of an animal. No, this thing, whatever it was, was much, much bigger than that. Sensing the lure of adventure, Luffy bolted toward it, the pack on his back clanging with each step.
As Luffy approached the source of the sound, the air around him grew cool and moist. Plain dirt gave way to soft and spongy moss. Luffy shouldered his way through a few low-hanging tree limbs and burst abruptly into a clearing, skidding to a stop just short of the edge of a lake.
Standing tall and proud before him was the most magnificent waterfall he had ever seen. In fact, it might as well have been the only waterfall he’d seen. Sure, he’d played in the creek back home plenty and explored every inch of its shore, but the little rapids that formed between its rock piles might as well have been raindrops on pebbles compared to this. A large, deep pool had formed at the foot of the falls, and beyond it, a slow-flowing river snaked its way back into the forest. Luffy closed his eyes as a shift in the wind bathed his face in a refreshing mist.
“They say it’s the tallest waterfall in the country,” Ace said behind him.
Luffy didn’t start at the sudden appearance of his brother. He was used to it by now.
“Really?” he said, casting a glance over his shoulder at Ace.
“Really really. Now c’mon,” Ace said, smacking Luffy’s pack with a thunk, “I’m starving. I’ve been waiting for ages.”
Luffy reached out to smack Ace in turn, but he was just out of reach. “You’re the one who ran off!”
“Had to make sure you could hang,” Ace said. “Now come eat before the ants get it.”
Together they unloaded a vast picnic from their packs. There were snacks and sandwiches and fresh vegetables and even a whole watermelon, and, most importantly, a whole roast chicken they had cut into quarters and jammed into the largest containers they could find. They had made the picnic together that morning, which was to say that Ace made it while Luffy sat on the counter swinging his feet and trying to guess where they were headed. His sole job had been to make the lemonade which Ace now distributed evenly into two colorful plastic cups, one of which he handed to Luffy.
“Hang on,” Luffy said just before Ace could take a sip. “Shouldn’t we drink to something?”
“Like what?”
“Like…” Luffy thought for a moment, then raised his glass. “To brothers!”
Ace laughed. “To brothers,” he agreed, clinking his cup against Luffy’s.
Though Sabo had left the island the year prior, Luffy could almost imagine him toasting alongside them. The thought warmed his chest as he and Ace each took a swig. Immediately, Ace began to cough.
“Dude, is there sugar in this?” Ace wheezed.
Luffy’s eyes watered as he spit his mouthful into the grass. “I forgot!”
They stared at each other for a moment, then burst into giggles. Three rapidfire games of rock-paper-scissors determined that Luffy would have to chug his cup. Holding his nose, Luffy polished it off while Ace laughed at his sour expression.
“You should work on your poker face,” Ace said. “You stick your tongue out when you’re gonna pick rock.”
Luffy smacked his lips as his taste buds danced. “Do not!”
“Do too.”
Luffy’s stomach rumbled loudly as if to voice its own opinion. Too hungry to squabble any longer, they dug in. Luffy was often yelled at for being a messy eater at home or at school, but Ace didn’t complain when they were alone. He didn’t tell him off for talking with his mouth full or scold him for wiping his fingers on the picnic blanket. That was one of his favorite things about hanging out with Ace: he could just be himself. When they were together, they made their own rules.
“You got something,” Ace said when they were done eating, acting out wiping his mouth.
Luffy rubbed blindly at his lip. “Where?”
“Right there,” Ace said, leaning forward as if to get it for him. At the last moment, he flicked the tip of Luffy’s nose instead, making him sneeze.
“Hey!” Luffy cried, and he lunged at Ace.
What started as a simple squabble quickly turned into a full-blown wrestling match. Ace caught Luffy by the hair just as Luffy’s palm smashed into his cheek, holding him back to keep him from landing any more blows. Hands scrabbling uselessly in the air, Luffy’s grunts of frustration abruptly turned into laughter when Ace jabbed a finger into his ribs, right where he was most ticklish.
“Now you’re just—playing dirty,” Luffy gasped between giggles.
“No rules against it, are there?” Ace said smugly.
Luffy tried to muster a response, but he was laughing too hard to get a word out. Ace seemed to take pity on him, letting him go for just a moment so he could catch his breath. But Luffy had never been one to waste an opportunity, and he took this moment to launch himself across the blanket in an attempt to tackle Ace. What he hadn’t taken into account was just how fast Ace was. Ace leaned out of the way, then surged after him as he tumbled onto the blanket, pinning him to the ground by the wrists. With a frustrated grunt, Luffy struggled fruitlessly for a few moments, then went boneless.
“I win,” Ace said, grinning fiercely. “How many is that now?”
Luffy’s nostrils flared. “One thousand and four.”
“One thousand and four,” Ace mused. “You wanna try again? Round it out to a thousand and five?”
“How ‘bout one thousand and four to one?” Luffy countered.
With that, Luffy yanked a wrist upward, putting Ace off balance just long enough for him to dig his knee into Ace’s stomach and shove him away. Ace rolled onto the blanket with an oof, and Luffy was quick to follow, plopping firmly down into his lap and jabbing him in the ribs with his fingers. To his surprise, Ace chuckled. Luffy grinned wickedly, exploiting this newfound weakness of Ace’s until his chuckle had grown into a full-blown laughing fit, not letting up until Ace begged him to stop.
“Okay, okay, you got me! Cut it out!” Ace exclaimed, breathless but smiling.
Luffy gave him a skeptical look. He half suspected that Ace had just been humoring him. It wasn’t the first time he’d tried that move, but it was the only time it had worked.
Ace set his hands on Luffy’s thighs and squeezed. “Now what?”
All at once, Luffy felt as if ice water had been poured down his spine. One thousand and five wrestling matches, and yet not one of them had felt quite like this. Ace’s keen gaze felt unfamiliar and strange, like Luffy was looking into someone else’s eyes. And beneath his ass he felt something stirring—something hard.
“You let me win,” Luffy blurted, clambering off Ace with legs like jelly.
“Did not.”
“Did too.”
Luffy stood up clumsily and headed for the water, his palms sweating as he tried not to think too hard about what just happened.
“Seriously, when have I ever let you win? I didn’t even let you follow me here!” Ace called after him.
Luffy gnawed on the inside of his cheek. He couldn’t deny that. In his mind’s eye, the strange look Ace had given was replaced with his more familiar competitive one. Maybe he’d just misinterpreted it. That bulge, however… Luffy gulped as the memory of it brushing up against his ass made him feel hot all over.
“I’m gonna swim,” Luffy said, shucking his shirt and shedding his shorts, leaving only his boxers on.
“What about your swimsuit?”
“Don’t need it!” Luffy said. He glanced down at the tent in his boxers. What he really didn’t need was for Ace to see it.
Ace chuckled, none the wiser. “Suit yourself.”
As Luffy approached the edge of the lake, he was transfixed by the sight of sunlight reflecting endless patterns through the rippling water. A wave of mist wet his face, cooling his burning cheeks. What he really needed, he figured, was a proper adventure. After years of searching for this place, it was high time for him to explore it. Scanning the shoreline, he spotted a huge rock jutting out high above the surface of the lake. He grinned. He knew just where he wanted to start.
Circling the rock, he found a set of sturdy-looking vines and tugged. Years of following Ace—or failing to—had taught him to be thorough in situations like these. When they didn’t budge, he grasped a vine in each hand and began the slow climb to the top of the rock.
A quick glance back at the forest floor earned Luffy a glimpse of Ace’s bare ass as he changed into his swimsuit. Luffy looked away, swallowing hard. Growing up, they had done everything together: they had changed, bathed, and even slept side by side. So why was he suddenly feeling so weird about it? Was it he who had changed, or had Ace?
Fueled by a potent mixture of confusion and determination, Luffy quickly ascended the last few feet up the side of the rock. A cool, fresh breeze swept over him as he emerged at the top, so high up he could see clear over the canopy. This rock was a lot taller than he’d thought. His whole body thrummed with anticipation as he toed the edge, a stray pebble careening off the top and into the water far below.
“Luffy!” Ace called as he waded into the water. “Don’t tell me you drowned.”
“Up here,” Luffy said.
Ace looked around for a moment, then up. His expression shifted from surprise to amusement to a sort of easy pride as he said, “There are rocks under the surface, you know. Don’t crack your head open.”
“You’re just jealous ‘cause you didn’t think of it first,” Luffy said, puffing out his chest.
“Bud, I’ve jumped off that thing more times in an afternoon than years you’ve been alive.”
Luffy snorted. Now he was just bragging.
“Go on, then,” Ace continued, folding his arms. “Let’s see it.”
Confidence surged through him at Ace’s goading tone. He positioned himself at the edge of the rock, imagining himself hurtling through the air, momentarily weightless and utterly free. It sure was a long way down, but the thought only served to excite him further. Taking in a big breath, he braced himself and jumped.
“Do a flip!” Ace called as he rocketed toward the water. Never one to resist a challenge, and especially not a challenge from his older brother, Luffy tipped his head forward. But the timing was all wrong, and he only got about halfway through the flip before he hit the water squarely on his back.
His senses came back to him in waves. First, he felt a flash of pain as his tender skin flared hot and red from the impact, stinging as it clashed with the water’s icy chill. Then he heard the muted mumble of the falls, so loud it rumbled his bones, yet so steady he could have fallen asleep to the sound of it. He opened his mouth to let out a burst of air, and a taste of murky freshwater touched the tip of his tongue. Next, he opened his eyes. Tiny glimmering bubbles clung to his eyelashes and rose to the surface, mingling with the rainbows of dappled sunlight churning with the waves. Small, shiny fish darted away from him, startled by his sudden appearance in their world. He shivered as one of them brushed by his bare ass. He frowned. That didn’t seem right…
Looking down, he was met with the sight of his own dick bobbing up to meet him. His eyes widened. His boxers. Where did his boxers go? No sooner had he turned to look when his head broke the surface, gasping for air as he realized just how desperate he was for it. His whole body shook with the cold as he turned in place in search of his boxers and came face to face with Ace. Ace’s eyes were screwed shut as he slicked back his newly-wet hair. He must have been caught in the wave from Luffy’s impact.
“You did that on purpose, didn’t you?” Ace said accusingly, but he was smiling.
“Y-Y-Y-You bet,” Luffy said through chattering teeth. He looked around, but he didn’t see his boxers anywhere. Maybe the current had swept them down the river.
“Looking for these?” Ace said, clearing his throat.
When Luffy looked, he saw his boxers held up high above Ace’s head.
“Hey! Give them back!”
“No way. This is payback for getting me all wet.”
“You were gonna get wet anyway!” Luffy roared as he lunged at Ace.
It wasn’t about the boxers—not really. It was that Ace had provided him with yet another challenge, and this time, Luffy was going to win fair and square. But as he attempted to wrest the scrap of fabric out of Ace’s grip, Ace’s superior strength and longer arms continued to prove a problem. Ace tossed the boxers from one hand to another, forcing Luffy to jump back and forth. He hid them behind his back, and Luffy tried to reach for them, but Ace yanked the boxers backwards just out of his grasp. Luffy spilled into his lap with a giggle, hardly aware of himself as his fingers slipped on Ace’s water-slick skin.
“C’mon, Ace, give them back!”
“They’re right here, Luff. Come and get ‘em.”
Luffy braced himself and made one last desperate lunge, but his foot slipped on a slimy rock, sending him crashing toward the rocky wall forming one edge of the lake. Ace caught him before he could collide with it, pulling him down firmly into his lap.
“Careful. Wouldn’t want you to get brained,” Ace said, grasping him firmly so he wouldn’t slip.
Luffy wanted to retort, but the familiar comfort of Ace’s embrace disarmed him. Reluctantly accepting another loss, he relaxed into Ace’s hold, his arms coming to rest around Ace’s shoulders, his breaths evening out as his heartbeat slowed. But part of him didn’t seem to get the message. Luffy stiffened as he realized just how excited he had become from their play fight. With no cloth to cover him, his cock had been free to rub up against Ace with every slip and slide during their scuffle, and now it sat, swollen and hard, pressed against Ace’s belly.
His heart lurched. He attempted to swim away, but Ace caught him by the hips and pulled him back down into his lap.
“You gonna run?” Ace teased. “Didn’t know you were a scaredy cat.”
Ace’s gaze was heavy on his face as it searched for his eyes. Luffy’s chin jutted out as he met Ace’s eyes defiantly.
“‘M not scared,” he mumbled, his cheeks burning.
“Yeah? Prove it.”
Luffy started as he felt Ace’s rough, warm palm wrap around his shaft. He struggled not to break eye contact as Ace rubbed the pad of his thumb across the head of his dick in slow circles, sending a shiver down his spine.
He understood on some level that brothers were not supposed to touch each other like this, or even really to acknowledge the need for this kind of touch in the first place. He had learned that the hard way when he’d walked in on Sabo in the shower, who had emphatically told him to “knock next time!” Or another time, when Ace had brought home a girl and firmly told Luffy to get lost. Now, suddenly, the rules he thought he understood had been turned upside down, leaving him feeling confused and a little scared. But Ace was older and smarter than he was, and he would never do anything to hurt Luffy, so if it were really so wrong, then why would he be doing it?
Luffy tensed as the rough pads of Ace’s fingers brushed along the length of his cock, then pulled back his foreskin, exposing his sensitive head to the cold water. He took a deep, shaking breath, not quite knowing what to do or where to look.
“Relax,” Ace murmured. “Feels good, right?”
Luffy nodded emphatically, closing his eyes as Ace began to work his hand rhythmically up and down his shaft. All he could think about was how badly he wanted more, more, more. Leaning back, he braced his hands on Ace’s knees and thrust into his grip.
“Ace,” he moaned, hardly recognizing his own voice. He’d never been touched like this, never spoken this way to anyone.
“Almost there, huh?”
Luffy made only a desperate, pleading sound in response. His head lolled back as the sensations overwhelmed him, and it was all he could do to chase them, to get to the place Ace wanted to take him. He ground down into his brother’s lap, then arched into his hand, moving entirely in pursuit of gratification. Suddenly, Ace’s grip on him tightened, and a bolt of pleasure shot straight to his groin.
“Ace—!” he cried, his voice breaking as he spilled into his brother’s hand. Ace stroked him all the way through it, murmuring sweetly, one word indistinguishable from the next. It was only when his thighs began to twitch and tremble uncontrollably that Ace finally let go of him. He collapsed into Ace’s lap, resting his forehead on Ace’s shoulder. When he opened his eyes, the first thing he saw was his own seed, white and goopy beneath the water’s surface. Something shifted deep in his gut as he was hit with a sudden clarity of what they had done; of what, based on Ace’s movements, they were still doing.
“Ace…” Luffy said, his voice quivering as Ace gripped his ass hard enough to bruise and rutted against it.
“Hang on,” Ace huffed. “Just—just a minute.”
Shame and doubt burned across Luffy’s cheeks as his brother’s hips arched against his own. It didn’t feel right—didn’t make him feel good inside, to see Ace like this. But he didn’t want Ace to accuse him of being a spoilsport, so he shut his eyes and endured it, burying his face in the crook of Ace’s neck, hoping it would be over soon.
Not long after, it was. Ace’s voice quivered in his ear as he grasped Luffy close and arched his hips one last time, heat and wet pooling in the cleft of his ass. Ace hugged him tightly as he caught his breath, his dick rapidly softening beneath him. They sat there for minutes afterward, just breathing. Slowly, the feeling of panic ebbed away, replaced by a sense of relief that it was over.
“Hey,” Ace said, jostling him. Feeling almost as if he were waking from a dream, he sat back and met Ace’s eyes. Ace reached a hand up to his face and swiped away a tear. Luffy was shocked to see it there, to find that his eyes were wet without his knowledge.
“Don’t tell anybody about this, okay?” Ace said, rubbing circles into his cheek with his thumb. “Not Dadan, not Sabo. Not anybody. It’s our secret.”
“I’m not a tattletale,” Luffy said, his voice strangely watery despite his obstinate tone. “You know that.”
Ace looked at him for a long moment, as if deciding whether to believe him.
“Damn straight,” Ace said finally, ruffling his hair. “Hey, by the way, I’ve got a surprise for you.”
That perked Luffy up. “What is it?”
Ace grinned. “How’s cake sound?”
Luffy’s eyes went wide. “You brought cake?”
Ace shifted Luffy off his lap and waded toward the shore, adjusting himself in his suit along the way. “‘Course I did. What kind of party would it be without cake?”
“What flavor is it?” Luffy said, chasing after Ace.
“C’mere and find out,” Ace said. “Oh, and here. Don’t forget about these.”
He tossed Luffy’s boxers over his shoulder. Luffy barely managed to catch them, water from the fabric spraying his face as they hit his palm with percussive force. He laughed, blinking the water from his eyes. As he tugged his boxers back on and joined Ace on the picnic blanket, the way he’d felt just minutes before seemed so distant and strange, almost as if he had imagined it. Ace was his big brother, after all, and he would never do anything to hurt him.
Would he?