I like the pose but I feel as if the only light in this photo is from the flash(on board judging by the catch light in the center of his pupil). IMO, fill flash technique refers to balancing ambient light with the light on your subject- often to avoid silhouetting of the subject. You can soften the 'deer in headlights' look by bouncing the flash off of a wall, ceiling, or other reflective object(friend in white shirt for example).
Nice pose. Lighting is too harsh for my description of fill flash. The shadows on the back wall are too harsh. This would have been great if done outdoors at a cematary, or a place to mimic a cematary, with a well exposed background and less flash.