1girl, 2015, backless dress, backless outfit, bangs, black dress, blush, breasts, brown eyes, brown hair, bug, butterfly, character name, dated, dress, from behind, happy birthday, holding, holding microphone stand, kisaragitsubasa, large breasts, meiko (vocaloid), microphone stand, open mouth, project diva (series), red headwear, short hair, shoulder blades, sideboob, solo, vocaloid