Boy character

The main action in this scene is emma's character putting their arm around Becky.
This is emphasised in the first half of the footage with the use of anticipation. The anticipation is created through emma's glances and

Note emma's body position, she begins further on her seat as her courage builds and she follows through with the action her position shifts physically closer to Becky.

 On the build up to the action, Emma makes 5 clear glances to her surroundings, this indicates her awareness of her surroundings and possibly her insecurity in the action she is about to perform which the lack of eye contact and initial hesitancy also suggests.

The completion of the action is signified by Emma's smile as her arm rests round Becky, we can also read this as relief, as the tension from Emma's body is released in this position (note the free hand drop as a sign of relaxation).