9ml, atsuko (blue archive), blue archive, game asset, highres, official art, third-party source, 1girl, armpit cutout, atsuko (leotard) (blue archive), black leotard, breasts, closed mouth, clothing cutout, covered navel, full body, hair between eyes, halo, heattech leotard, leotard, long hair, long sleeves, medium breasts, purple hair, red eyes, simple background, socks, solo, standing, tachi-e, transparent background, turtleneck, white halo, white socks