This would be pretty daring for the film project, but honestly, it’s the way I would do it… no matter what the length of the film needs to be.. 5 minutes, 1 hour (1 hour would drive the point home & really deliver the experience I am going for)... have the two sitting on the floor in a dimly lit room, their backs pushed up against one another, barely audible music in the background & have them do absolutely nothing for the entire film. They can have natural body reactions, cough, sneeze, scratch their nose, yawn, pick a scab thats on the back of their hand. But for the entire time, they never turn around, they never look at each other, they never get up & they never look bored… just – content. The camera should never move either. Just the side shot, with the two of them square in frame. Make it feel like the audience is sitting in the room with them. Let the audience experience what the boy & girl are experiencing.
A great friendship allows for comfortable silences. If you feel the need to talk, just to make noise & avoid the awkwardness of the still & quiet… then your not really comfortable being alone with the person.