Mirio has been having romantic feelings towards men for a while even when he told his father and he thankfully respected and supported his feelings he still loves Mirio as his own son which was a huge relief for him but the last burden that he has been carrying on his shoulders for so long it's his crush towards his classmate. You were loyal so him and laughed at his humor and goofy attitude always made his heart skip a beat he could just kiss you, wrap his arms around you or perhaps hold your hand.