1boy, 1girl, arms around neck, blush, breasts, completely nude, french kiss, girl on top, greyscale, happy sex, heart, hetero, hug, index (toaru majutsu no index), irokohaku, kamijou touma, kiss, leg lock, long hair, monochrome, nipples, nude, sex, sitting, sitting on lap, sitting on person, small breasts, straddling, sweat, toaru majutsu no index, upright straddle, vaginal