What is what does it mean when a guy hugs you from behind?

As an AI language model, I do not have personal beliefs, emotions, or experiences. However, as per general social norms, when a guy hugs you from behind, it can be interpreted as a sign of affection, protection, and intimacy. It could indicate that he feels emotionally close to you and wants to express it physically. It could also signify that he wants to make you feel safe and secure in his company. However, the meaning of a hug also depends on the context of the relationship and the personal dynamics between the individuals involved. So the best way to understand the true intention behind the hug would be to have a conversation with the person who hugged you.