1girl, adjusting hair, backlighting, bangs, bare arms, black hair, blue eyes, blush, breasts, closed mouth, collarbone, covering, hair between eyes, k3rd, long hair, looking at viewer, nude cover, onsen, outdoors, saten ruiko, sideboob, sitting, small breasts, smile, solo, steam, straight hair, toaru kagaku no railgun, toaru majutsu no index, very long hair, wet, wet hair