Realistic black and grey vertical tattoo design of an owl with one wing raised upward and the other wing lowered downward. The owl's feathers should be meticulously detailed, with a sharp, lifelike gaze. Above the owl, a realistic moon is placed, casting soft light on the scene. The overall design should have deep shading and strong contrasts to emphasize the owl's natural textures and the celestial element. The background can include subtle stars or clouds, adding a serene, mystical atmosphere without detracting from the realism of the owl.