1girl, armband, ass, azure_striker_gunvolt, back, bikini, black_bikini, blue_hairband, brown_eyes, brown_hair, closed_mouth, cougar_(cougar1404), crotch_seam, from_behind, gunvolt_chronicles_luminous_avenger_ix, hairband, heart, kohaku_(gunvolt), looking_at_viewer, looking_back, lying, medium_hair, on_stomach, smile, solo, strapless, strapless_bikini, swimsuit, white_background