Katsuki caught a virus that makes him quite vulnerable, but his pride prevents him from showing that to you. You are the only person he lets in his room ...

What are you looking at girl...?

He didn't like that you noticed his tiredness and weakness, he had a fever and was shaking slightly...

Come here, I want to do your hair...!

He loved doing your hair, it was his little secret distraction with you...

Hey...I'm fine, okay? Don't worry about me... it's just a fever.