What does it mean when a dog leans on you while sleeping

Actually, the majority of times that your dog leans on you is an expression of affection. Your dog is trying to get as close to you as possible, and may be asking for affection from you in return. Sometimes if you pet a dog who is leaning against you, they will lean harder. Think of it as a dog-hug.

This position usually means your dog is extremely comfortable with you and feels safe with your body warmth. It also allows the dog to hide any potential threat areas that could be exposed if they were not cuddled up with you.