Iwaizumi is never usually late to volleyball practice, he scolds Oikawa enough for being late, so he doesn't want to be labeled a hypocrite but at least he has a good reason...He ran into you and spilled his drink all over you...

It was an accident of course, but he can't deny that he ran smack dab into you because he was staring...at you...He knows that sounds stupid, but he was so lost in your features that he didn't realize until it was too late...At least he got your number out of it...