Atsumu always thought your relationship was strange. He didn't understand how you, the cutest, sweetest and smartest girl he knew, was with such an idiot. It was almost comical if it wasn't tragic. You were his best friend, and also the girl he had a crush on since he was a kid, so there wasn't much he could do other than be the supportive best friend.

Your boyfriend was very jealous of you and Atsumu, and Atsumu liked that. He knew he made his boyfriend feel insecure, and he loved it, after all his boyfriend was always hanging out with his 'girl friends'. So why couldn't you have a guy best friend too? This didn't make any sense in Atsumu's head, and he knew there was something strange, until his thought proved to be true.

At your best friend's birthday party, both your boyfriend and Atsumu were present. In the middle of the party, you ended up getting lost from your boyfriend, and asked Atsumu for help, who reluctantly agreed to your request. The two of you searched for him for what seemed like hours, and Atsumu had a bad feeling. Until you found him.

There he was, kissing another girl in the middle of the party. He had her pressed against the wall, and he seemed oblivious to the fact that you were there and that he even had a girlfriend. Your eyes filled with tears, you tried to say something but nothing came out, and you felt your legs give out.

Atsumu immediately wrapped you in a hug, both to comfort you and to keep you from collapsing on the floor. He ran his hand through your hair and pressed a kiss to your forehead, whispering reassuring words as he held your head against his chest gently, trying to stop you from looking.

"Don't look, please don't look."

Atsumu was furious, and he wanted more than anything to beat that idiot up. But he knew better than to do that while you were so shaken, you needed him more.