Warning: this contains SUPER FLUFFINESS!. i think.
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"SUGWARA-SAN!!!!" Hinata shouted with tears in his eyes and was running away from a devil. Kageyama "Get back here you brat!" HInata tripped over a cord and fell down with a bleeding scrape, he sniffled crying loudly. Kageyama advanced forward and leaned down glaring and lifted up the 5 year old's leg and licked the scrape, a chill went up the boys back. Kageyama "Be careful, Brat." The two boys heard loud hasty footsteps and Sugawara came into view breathing heavily "W-what?..i heard yelling!" he eyes locked on Hinata's wound and ran into the bathroom and got a bandage and came back and sat Hinata in his lap "What happened Hina?" he sniffled "I-i tripped! over a cword.." Sugawara chuckled at hinata's cuteness and put the bandage on. Kageyama was pouting and striving with jealously but held back and just puts a glare on. Sugawara put hinata off his lap and ruffled his hair and kissed the boys cheek "Be careful okay?" He said sweetly with a bright smile on his face. Hinata looked up at him and smiled brightly "Hai!" Sugawara nodded and went off into the kitchen leaving the two boys alone.
Hinata then looked at Kageyama, Him doing the same and they both glared at eachother. Hinata "I hate you you idiot!" he ran into there bedroom and jumped on too his bed. Kageyama following "You don't hate me, Brat." "I do too!" he pushed his face into the pillow. He felt his bed creak and he slowly turned his head a little and saw kageyama on his bed looking at him "Don't forget my promise to you." hinata "........that promise?." he blushed a little. Kageyama looked away "I intend to keep it! I intend to marry you! when we get older!" Hinata blushed a little brighter "S-shut up idiot..." Kageyama grabbed his shoulder and gave him a peck on hinata's lips, Hinata blushed heavily "w-what was that for?!..." Kageyama "I love you." he brushes his thumb against hinata's cheek. Hinata put the blanket over his head and went to sleep blushing, Kageyama smiled softly and climbed into the bed with him.
~half a hour later~
Sugawara came to tell the kids its time for dinner but didn't find them anywhere and looked into their room and saw this.
Sugawara fangirled a little and took a picture 'so cute~' he put it as his backround and walked out of the room and said "Goodnight Kageyama and hinata~" and ate dinner alone and but the two boys plates in the fridge so they could eat it later!.
~Huge timeskip to when they are adults~
Hinata was reading Volleyball comics on the couch of his apartment and got up when he heard a knock on his door he lazily dropped his comic onto the coffee table and walked to the door but looked out the window to the side 'its snowing..' he thought happily and opened the door and saw..."Kageyama?" He smirked "Who else?" hinata couldn't help but blush and cover his face "What are y-you doing here?." he walked out and closed the door behind him and looked up at the tall adult. Kageyama "I came here to say i love you ofcourse" His eyes widened..Kageyama has said that many many times but he didn't really believe him. Kageyama took notice of this and leaned in and kissed the boy, Hinata didn't know what to exactly do...but he kissed him back they parted lips "I love you too...Yama.." they kissed again and Kageyama wrapped his arms around hinata's waist and Hinata's arms around kageyamas neck. little did they know sugawara was not far away from them behind a corner acting like a stalker while talking pics fangirling loudly in his mind 'SO FACKKKIIINGGGG CUTE!'
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Hope you enjoyed
Me while writing this:
Don't judge but I WANTED SO FACCCKKKINNNGGG BADLY TO MAKE THIS A LEMON! *wiggles fingers in a creepy way* and make the stalker Sugawara record everything and show it to them~~~~ i really wanted to do itttt but i wanted the first chapter of my otp to be a fluff