This was really pissin' him off.

He was trying to train and test out some new moves, but your useless ass kept distracting him!

How the hell can't someone tie their hair?!

After seeing you in the corner of his eye struggle to out your hair up, (you were trying to make it look good, he guessed. you've done it like fifteen times over..) he had enough.

"OI! Give me the damn rubber band, idiot!" Katsuki barked as he stormed over, wearing his usual annoyed scowl.