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Luffy’s rubbery-soft hands clasp Ace’s fingers as they pull him through the forest. They’re icy in the evening, but Ace’s furry hands run hot like his blood flows with fire, so they warm up his little brother too. Luffy’s bringing him out to show him this flower that blooms at midnight, something he learnt from a conversation with one of the bandits who has a particular interest in botany. It’s not too dark for them to be wandering aimlessly through the forest, fireflies dancing between leaves and the moonlight reflecting onto the shiny blades of grass that highlight Luffy’s path up the mountain.
The night should feel perfect. But there’s this hum under Ace’s coat of fur. His hackles are up, but he doesn’t sense any external danger, no tiger or bear in the vicinity. When Luffy drags him along, the buzzing grows louder.
“Where’s the flowerbed?” Ace asks. He needs to scratch this itch soon.
“I think it’s across the bridge. Then we have to go up to the cliff of the mountain,” Luffy says. His tiny fingers squeeze around Ace’s, rubbing them for warmth. Then he repositions to intertwine their fingers.
Ace looks up to the sky. Between the shroud of the trees, he can see glimpses of the full moon flickering in and out, obscured by the rustling leaves. When the gaps between trees reveal more of the moon, his head throbs, little pricks digging into his brain like a pincushion. He looks away, trying to focus on anything else, and chooses to stare at the way Luffy’s slender, small hand is locked with his furry, larger one. Observing how fundamentally different they are as brothers, but Luffy still wants him to be his family.
They cross the log over the fissure that splits the mountain apart, and Luffy leads him down the slope. But as much as Ace tries to focus on anything else, the peculiar feeling doesn’t leave. In fact, it gets worse.
“Luffy, how much longer is it? I’m-there’s something weird happening to me.”
“Maybe a few more minutes? It should be really close.” Luffy peeks out of his periphery at Ace. “What’s wrong?”
“Nothing… just a headache. I just want to see the flowers now.”
"I'll get us there as soon as possible!" Luffy says.
But then he stops in his tracks, looking from side to side.
“Uh… I might’ve gone the wrong way though.”
Ace groans.
They enter an open patch in the forest circled by a ring of trees, empty save for a few rocks and weeds. It’s lit up by the moon, shockingly vibrant with no foliage in the way. Luffy hums to himself, deciding on a direction, while Ace fends off the sharp pain in his head.
It’s too much. Ace pulls his hand back and grabs his skull.
“Augh!”
“Ace?” Luffy turns to him.
Ace clutches his head, but the pain is spreading, all the way to the ends of his limbs. He looks at his hands. They’re quivering, but that’s not the only thing that’s wrong. His fur is growing longer.
“What’s happening?!” Luffy asks. He runs up to Ace, grabbing his shoulders.
I don’t know! Ace wants to say, but he’s lost his voice. He falls, ground hurtling towards his face. He catches himself with his paws, but he gasps when they come into view again. He’s turning white. Not pale, like a sickness, but white like the moon. His nails are sharpening into daggers. White tendrils climb into his periphery and he runs his claws through it, tugging it and feeling the pull from his scalp.
“Ace, you’re-!” Luffy gasps. His hands slip off. Ace tilts his head to look at him, but his eyes widen. Luffy looks so small underneath him. Smaller than he usually is. Is he shrinking?
Ace glances at his surroundings, the grass, the rocks, the trees. No, everything else is smaller too. He can feel his shorts stretch and stretch around his thighs and crotch until a splitting tear rips through the night.
He’s growing.
But the pain makes all of this negligible. It calls for one solution only, to tend to the burning in his heart and guts.
“Are you okay?” Luffy asks. He looks hesitant, but he hasn’t backed off. He grabs Ace’s paw and rubs his thumb over the back of it.
Ace tries to speak, but his body acts first and pushes Luffy into the dirt. Luffy’s mouth opens up to gasp or shout or yell, but Ace’s maw slots itself there, taking advantage of the opportunity. He sticks his tongue down Luffy’s throat, feels his little brother scream around it. Ace just moans. The vibrations egg him on. Even when Luffy gains control of his body again and starts trying to shove Ace away, it just makes him more wired. Electricity is running through his veins.
He humps up against Luffy’s legs. He can tell that his penis is fully unsheathed, the red flesh much more sensitive without his fur in the way. The tip jabs at Luffy’s thigh, and he squeals right into Ace’s mouth which he devours like food.
The denim cloth feels coarse against his dick. Ace hates it. His nails slash away at Luffy’s shorts and shirt, ripping them into tatters. Luffy wails, even though Ace is sure he didn’t scratch him. And if he did, it would only be skin-deep.
Now he can freely jab at Luffy’s slit, edging it open like he would with his fingers. Ace thrusts it inside deep without preamble and Luffy screams. Despite this not being Luffy’s first time and even though he’s made out of rubber, the sudden insertion is still harsh for him. Not for Ace, though. He feels wonderful.
In this newfound form, Ace finds himself plunging faster and harder into Luffy. Something about him feels awake, like he’s opened his eyes for the first time. He feels so much more too. More of the air around him, the grass under his feet, the space inside Luffy. It’s all dialed up to a hundred, and another hundred more.
He presses the flare of his knot at Luffy’s cunt, wiggles it around like it’ll ease the way through. It gives way after a few thrusts, Luffy’s pussy used to the abuse. It closes around the base of his knot and Luffy chokes on his spit and Ace’s tongue.
Ace cums thin streaks in Luffy. His hips rock against his crotch as if it’ll go any further in, when Luffy’s already at full capacity. It’s always a treat when he gets to bully it in. He licks Luffy all over his face, grateful for letting his older brother fuck and knot him. Even if Luffy didn’t have a choice.
Ace lathers his tongue on Luffy’s cheeks, relishing the flavor of his sweat. The taste is especially salty, and he rears back to find Luffy sniffling, tears caught on his long eyelashes.
“I just wanted to see the flowers…”
Ace feels his heart break. He parts his lips, apologies ready to flood out, but only a snarl emits from the depths of his throat. With his dick cumming into Luffy, squirting at intervals, his mind clears up little by little. Hesitantly, he tries to tug on his knot to free Luffy, but it has never let go before and it doesn’t now. He looks up to the moon, watching as clouds start to wash over it. The flower might wilt if they get there too late.
He turns around on his knot, twisting his dick in Luffy. Luffy’s all ruined, so he barely flinches. Ace starts to drag Luffy by the knot, connected to him like an extra limb as Ace begins his trek. In this larger, stronger form, it barely takes any effort to take Luffy along.
Ace is pretty sure Luffy got the directions wrong at the very end, so he climbs up the mountain, hoping his intuition is correct. When he catches a glimpse of alabaster through the tree trunks, he knows he’s found it.
The view is breathtaking. Luffy wasn’t kidding. It was worth the late-night excursion.
He growls softly to alert Luffy, but Ace doesn’t get a response. He turns on his knot again to check up on him. Luffy’s eyes are closed. Ace frantically tries to lick Luffy awake, dragging against his eyelids with his tongue. He can’t miss the bloom now, after all the trouble Ace has put him through.
“Ugh…” Luffy whines. He blearily opens his eyes, blinking up at Ace. “What is it?”
Ace’s snout pushes Luffy’s face to the side into the bed of flowers. Luffy’s eyes widen and he gasps. Ace watches as he revels in the field of flowers around him, more than he could take in. Luffy looks so radiant, laid out in the soft pillowy bed, face full of wonder and pussy full of knot. Ace bends down to lick him again.