A while ago I saw a thing on Tumbler that was basically this and I had to write it because it came to me today and it wouldn't leave me alone until I wrote it. So here you are!
Disclaimer: I own nothing!
Poor Ron couldn't take it anymore and it was all Hermione's fault. It was during the summer holidays when all of the Weasley's were in attendance for once. Harry and Hermione were sitting off to the side as shirtless Weasley boys de-gnomed the garden. "I am liking this view." Hermione called with a giggle causing Fred and George to flex as Ron turned red.
"I'm not about to complain either." Harry said with a laugh as the twins blew kisses at him.
That was when Ron turned to his friends in confusion. "What? I thought you liked girls."
Harry shrugged. "I like blokes too." Hermione nodded as if to say "obviously" and no one else looked surprised.
"What! Since when?"
"Um, since always? I thought you knew." Harry said confusedly.
Ron turned around with a huff. "Now I have to watch out for you hitting on my brothers AND my sister."
Harry shared a grin with the twins and Hermione sighed. She could tell that this was not going to turn out well.
The next morning Ron came downstairs and saw Harry wearing a sweater with the letter G on it. Ron didn't think anything of it other than to grumble under his breath. "Obnoxious git. Shoving his relationship with my sister in my face."
As soon as Ron had a large mouthful of food, George leaned across the table to Harry. "So hot-stuff how's the sweater?"
Ron choked on his food before he cautiously peered at his friend and noticed with a slow horror that it was much too large and was probably George's. "What are you wearing that for?!"
Harry winked at the twin. "Well, the Weasley men are very attractive and George can be very persuasive."
Ron turned white. "No way! You're not dating George! I thought you liked Ginny!"
The girl in question giggled after a beat. "I mean we tried for a bit, but then we agreed that Harry is a much better match for George than me."
Ron nodded slowly and returned to stuffing is face with much more concentration than was necessary.
Later during the prep for the backyard Quidditch game Harry and George loudly proclaimed that they wanted to be on the same team today. "But we can't have Fred, George, AND Harry on a team! The other side would lose for sure!"
Fred shrugged with a well hidden grin. "I guess me and Gred can be on separate teams today." Ron just sputtered with his mouth open for a minute while everyone else nodded as if that was the most normal thing in the world. "Well now that that's settled we should start the game!"
That night Ron grimaced when he walked into the living room and saw Harry and a twin cuddling on the couch, while the other twin was messing with Hermione's hair. "Hey George I'm going to grab some drinks. Do you and Mione want anything?"
George looked up from messily braiding a mildly-annoyed Hermione's hair. "I'm fine. How about you?" He says to the brunette sitting near him. She makes an affirmative sound as she swats away George's hands.
Fred looks up from the couch that Harry just vacated. "Do you want a drink Ronnikins? Harry is getting me, him, and Hermione something."
Ron just stared at his brother like a fish. "But-I thought… Harry and George..."
The twins shared a suggestive look. "Oh ickle Ronnikins, when have you-"
"-ever known us not to share?"
Hermione coughed to cover up her laughter and Ron turned white just as Harry re-entered the room. "I've got everybody a pumpkin juice."
The next morning Ron didn't come down for breakfast until it was almost over. He seemed relieved that Harry wasn't sitting in the lap of one of the twins or wearing one of their jumpers. Ron sat down and gratefully stuffed food in his mouth.
Ron almost choked when Harry spoke up. "So Charley, any girlfriend back in Romania?"
Charley grinned after a second. "Nope, no girlfriend."
"Well how do you feel about long distance relationships?"
Charley laughed, a great booming sound. "Well it might bring me back home more often."
Ron stood up and stormed off with a cry of "this is ridiculous!" as the rest of the table dissolved into laughter.
That became the running joke for the rest of the summer and it was all Hermione's fault.