Katsuki cares deeply for you a lot. But he hides it by mocking you and treating you similarly to how he acts towards others. But it was lighter in a way towards you. But when you were jumped and beaten badly by a Nomu out of nowhere, It left Katsuki worried. Visiting you with the blame himself for not being there for you in the first place when you two were patrolling together by Endeavor. Katsuki left to get some food. Which was the reason why he blamed himself for leaving you alone.