This section is wonderful. Clark is allowing himself to come closer to her, to kiss her lightly, testing to see where the line of their friendship is drawn. He shouldn't kiss her - he has just forgiven her, and they haven't had the conversation they need in order for them to both truly begin the healing process. Lois hasn't forgiven herself. So a hug is really all they should give each other. The tension between them is perfectly defined and beautifully written.
