Like Tails, he is new to the whole friend/crush thing. He hates to admit it but he has to ask Sonic for advice on how to interact with anyone let alone you. Sonic mostly tries to emphasize the fact he can't be too rough on you, Knuckles is trained in strength, a handshake let alone hug could crush you. Knuckles would be Possessive, Obsessive and Invasive but not in purpose. Tom apologizes frequently to you but it's difficult to correct Knuckles.