Hey hey hey! :D
I cheated a bit, as it was initially a drabble request. But this prompt for day 18 and step-brothers au blended well together so here you go!
Small, tanned hands gripped the hem of the woman's skirt as he hid his equally small body behind his mother's. He looked up hesitantly, meeting a soft smile of a redheaded man with forked brows.
The man laughed and crouched down to his level, extending a large hand for the boy to shake it, the gentle smile never fading from that face. Daiki snuggled closer into his mother's leg who watched the scene with an amused smirk.
The redhead tilted his head playfully, his smile getting wider as he encouraged the boy to take his hand for a handshake.
Daiki took a shaky breath as he hesitantly reached his small trembling fingers to man's hand. When the man grabbed his hand and gave a firm shake, Daiki's lips spread into a wide grin. He thought that his small hand fit perfectly in that warm, big, calloused hand of the redheaded man.
"Nice to meet you, Daiki." the man said, his other hand going to rest atop of his head, slightly ruffling his short blue hair, making the kid giggle.
"Nice to meet you, asshole!" Daiki beamed happily.
His mother let out a shocked gasp and scolded him "Daiki, watch your language! Who taught you that word?"
The kid looked up in his mother's eyes with an innocent look "Asshole? Is that a bad word, mommy?"
"Stop saying that, and of course it is a bad word, Daiki." the woman shook her hear exasperatedly "I bet you heard your uncle Shougo swearing again."
The redhead who didn't say a word until then, looking at the scene with warm eyes, laughed out loud, earning confused looks from both the mother and the kid. Daiki seemed to be in wonder rather than confused or surprised though.
"You both look so cute." the redhead said, wiping the corners of his eyes.
Both Daiki and his mother's eyebrows twitched at that "I'm not cute!" they both yelled and it caused another laugh escape the man's throat. He stood up and patted kid's head as he leaned to peck the woman's cheek. Daiki's mother blushed and touched her cheek avoiding man's brown eyes.
"Yes, you totally are."
Daiki watched the adults with interest and started giggling at his mother's reaction.
The man laughed at the boy while his mother smacked the back of their heads playfully.
"Here we go, Taiga." the redheaded man said and lifted up the baby "This is your older brother, Daiki. Say hello."
Small hands, smaller than his, were wrapped gently around his tanned fingers while a pair of crimson eyes watched him with curiosity. Daiki grinned widely and the small angel smiled back at him, making some incomprehensible sounds.
This was the first time they looked into each other's eyes, smiled at each other, held hands. Warmth spread into Daiki's chest, striking his heart on full force. This feeling was overwhelming, and the only things he could do were to smile wider and squeeze gently that little hand in his.
"Daiki!" a manly, rough voice echoed through the halls.
"Dad?" Daiki lazily drawled as he walked up to the source of noise "What is it?" he asked rubbing his eyes off sleep and yawning.
The man grinned "Pack your shit, son. We're going to fishing."
Daiki's navy eyes widened and lit up "Really? But aren't you supposed to work?"
His stepfather grabbed him by shoulder, pinching his cheek "I have a day off and I want to spend it with my family."
"Alright, old man." Daiki said and wanted to sprint upstairs but stopped when the man called after him.
"Daiki! Wake Taiga up and tell him to help your mother in the kitchen!"
Navy eyes rolled but he nodded anyway and went upstairs. Walking to his brother's room and knocking lightly, he frowned when he got no reply. He pushed the door open and walked inside, eyeing the bed.
Taiga slept soundly on his stomach, the blanket pushed aside. His shirt was rolled up to the middle of his back and his boxers did nothing to hide the perfect shaped ass. He had long strong limbs, sun-kissed skin and a truly handsome face.
Daiki gulped and looked away, in attempt to calm himself down. He reached a hesitant hand to Taiga's shoulder and shook it. The redhead mumbled something in his sleep, but didn't wake up. Even after five minutes of shaking and pulling hair, he didn't wake up. Daiki growled in frustration and slapped Taiga's butt.
Crimson eyes shot open and the redhead let out an unmanly yelp. He glared at Daiki as that started snickering "What the hell, asshole?"
"Pfff- hahah! Your face! Priceless!" Daiki laughed out loud.
Taiga's face darkened for a second but then he smiled at his brother. Daiki watched him confused.
Those strong hands he admired minutes ago grabbed him by waist and tackled him down on Taiga's bed. They started wrestling, punching and kicking each other playfully, grunting and panting in other's ears and faces.
They were a mess of tangled limbs when they stopped, laughing with joy. Their laugh died and they looked at each other.
Taiga was on top of Daiki, his face flushed, from their little wrestling match, with drops of sweat sliding down his neck. Daiki gulped. He wanted to lick it off Taiga's skin.
Taiga smirked down at him as if reading his thoughts. Then he did it. He pressed his morning wood into Daiki's crotch and grinded purposely, making the other gasp.
Daiki grabbed his shoulders, grunting in his brother's ear "T-Taiga… shit. Stop messing around, I didn't close the door."
Taiga put his hands on Daiki's hips and rubbed their clothed erections more fervently "Let's do it faster then… Daiki."
Daiki growled in frustration and pushed their boxers down so they could make skin-to-skin contact. Taiga's large hand gripped both of their erections and started pumping them in a fast rhythm.
Tanned hands grasped the redhead's shirt, nails digging into the soft fabric that hard it practically scratched the skin under it.
Taiga nibbled at his neck gently enough to not leave any marks, but Daiki knew that his brother hardly held himself back. He hardly held himself back too.
Soft pants and silent moans filled the room. Familiar heat enveloped both bodies as the boys found their release, jerking in each other's arms.
Breathing heavily, Taiga caressed Daiki's cheek and pushed their lips together in a slow, sensual kiss. Daiki loved when Taiga did it.
Taiga pulled away and pressed their sweaty foreheads together "I love you." he said while looking into those navy eyes with affection "I love you, Daiki."
Daiki's heart jumped in his chest and he slightly flushed. Taiga smirked, but then gasped when Daiki pulled him into a tight embrace.
"Dumbass." Daiki grumbled hiding his heated face in Taiga's shoulder "I love you too, sunshine."
Taiga laughed and it was that beautiful sound Daiki never got tired of. He flipped them around and gave the redhead a peck on the lips. Then he stood up and pulled his boxers back.
"Get ready and help mom." Daiki grinned "Dad takes us to fishing."
Taiga rolled his beautiful ruby eyes "Yeah, yeah. Fishing maniacs."
"Shut up." Daiki playfully kicked Taiga's leg and strolled out of room.
Taiga watched fondly his brother's back as that retreated. A gentle smile tugged at his lips as he mouthed "I love you."