Rule 34 Dev - 1girl arm_up bare_shoulders black_eyes breasts detached_collar detached_sleeves female_focus flower grey_background hand_in_own_hair happy_birthday headphones headset long_hair looking_at_viewer megurine_luka megurine_luka_(vocaloid4) mossan pink_hair simple_background smile solo sparkle upper_body v4x vocaloid|6746111424