Q1) In the context indicated "bond" does not mean the same thing as "connection" - "bond" implies a serious relationship, but here we're talking about an intense but not at the moment serious relationship. " Q2) "All one" is unusual and I'm 100% sure I understand it. What it seems to mean is that smile, warmth, friendship, connection, deeper meaning all create a unity (one is another word for unity) that is this one person.
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