So sorry to hear about Leo.
I don't like pets (sorry to say this) as it just feels so weird to touch something alive that is not a human being. Sometimes I wish I could get over that 'phobia' as I know some cats and dogs are adorable and are better friends than human beings. Just like Leo, I'm sure your bond with him is a lot stronger than with many human beings and his departure will leave a big hole in your heart.