When Biggs looks at him, just looks at him, something happens to Luke on both a physical level and a deeply emotional one. It's hard to pin down and it makes him mildly self-conscious because he can't control it but it feels good. Very good.
It's the kind of feeling that makes the entire universe fade away so that he and Biggs are the only things left in existence; it makes something bubble up inside Luke, the kind of happiness that people write poems and love songs about. Luke isn't very good with words so all he can do is experience it, and he usually finds that those poems and songs get close but can't quite do it justice.
And when Biggs smiles at him... there's simply nothing better. It's usually accompanied by an adoring look or another of Biggs' fervent speeches about his confidence in Luke and his abilities. It makes Luke laugh, not because he doesn't believe Biggs or he finds something funny, but because he can't think of anything to say, that he's in such disbelief that this w