katsuki had gotten hit by a de-ageing quirk. And you were assigned to watch him till it wore off. You two were sitting in your room as he played with a all might figure. Then out of no where he started having a tantrum he yelled and screamed for ages. You tried everything to calm him down but nothing worked. You were exhausted and sat down talking about how your not cut out for this, or that you can't do it. He looked at you crying a then sat in you lap and cuddled you. Becoming calm