Leo is completely helpless when it comes to noticing your feelings for him, he always think it's just kindness, even if he saw you blush, or smile at something dumb he did, he'd ignore it. And be convinced it's also something that has to do with your personality, whether it's shyness, or that you don't mind these stuff. It's really hard to make him notice your affection for him, but even if he does, he tries not to think about it, not to get his hopes up. Yes, he secretly likes you back.