While I loved everything about their “real first kiss”, one thing that really stood out to me was the look on Emma’s face when they break away from the kiss for a second. She looks so overwhelmed with emotions and the weight of their shared moment. As Jen said, she finally allows herself to be vulnerable around Killian and that’s exactly what you can see in her eyes here. You don’t even need to fully see Killian’s face to tell that the look he gives her is full of love and tenderness. When Emma sees these emotions shining back at her, combined with the knowledge that he gave up everything he had - his home, along with the last memories of his brother and his first love that were tied to it - for her without ever demanding anything in return, she can’t help but smile at him, because it feels so good to finally let go of the past and to finally be able to trust someone with her heart and her feelings again after such a long time.