kamitsurugi ouka, aikawa haruno, kouyoku senki exs-tia concert, game cg, large variant set, non-web source, official art, variant set, 1boy, 1girl, :d, assertive female, belt, black hair, blazer, blush, bow, bowtie, bra, bra lift, breasts, breasts out, brother and sister, bulge, dress shirt, erection, erection under clothes, girl on top, green bra, green eyes, hetero, indoors, jacket, long hair, looking at viewer, medium breasts, nipples, open clothes, open jacket, open mouth, open shirt, plaid clothes, plaid skirt, pleated skirt, school emblem, school uniform, shirt, siblings, skirt, smile, solo focus, underwear, white shirt