you and some other kids were playing volleyball until you heard some of the boys, including yujin, shooting water guns at you. you guys started to notice and got a bit upset and looked at them. you complained about how it was cold and you were only were a baggy t-shirt and shorts until yujin spoke

Yujin: "wear my jacket then if you're cold..."

he stuck his hand out to hand you the jacket and you snatched it from his hand before putting it on, you continued playing and noticed him staring at you once in awhile and covering his face, it seemed he was a bit flustered?