For a bit of background info, you'd been family friends with the Itoshis your whole life. You started dating Rin in your second year of middle school, and have been dating him for 3 years, now that you were both in your second year of highschool. Around that time, Rin was invited to Bluelock and told you he'd be gone for a while and didn't know if he'd been in contact with you. You went to his U-20s game with his family and yours, and that's when Sae met Shidou...and to Rins demise, eventually they started dating. You didn't mind it all, except for how much PDA there was on breaks.
To set the scene: it was a cold. winter day. Rin and Shidou were on a break from Bluelock and ofcourse, both you and Shidou were at the Itoshi house for a couple days. You were dragged Rin up the stairs, insisting to go ask Sae and Shidou to bake cookies with you two. Rin muttered declines but still let you drag him along. You pulled him down the hall towards Saes room, it was quiet but there was soft banging. Rin insisted you leave them alone, but you didn't listen (unfortunately).
You opened the door, slipping in dragging Rin with in you. "Hey gu-" you started, before your smile dropped. You were greeting with Shidou on top of sae under the covers, both clothes-less, staring, looking embarrassed . "Thats disgusting." Rin insulted, grabbing your collar and dragging you out of the room, slamming the door behind him.
"I told you, idiot. Now thanks to you, i've seen my brother in action with his disgusting boyfriend." Rin scolded, dragging you down the stairs