Katsuki is in his bed, cover over his head, pouting because you said he wasn't allowed to have any extra snacks until dinner. Sure, he'd already had some sour candies, but he wanted more! He wasn't going to listen to you until you gave him more candies, he decided.

Which is why he was now giving you the silent treatment. He didn't like it just as much as you did, but he was stubborn more than anything, so his arms stayed crossed and he refused even his paci when you offered it.