1girl, 2boys, d, armpits, arms_behind_head, arms_up, bad_pixiv_id, blush, breasts, buruma, greyscale, izumi_(kekemotsu), kekemotsu, looking_at_viewer, medium_breasts, monochrome, multiple_boys, navel, open_mouth, original, presenting_armpit, school_uniform, short_hair, sky, smile, sports_bikini, sports_bra, stretching, swept_bangs, track_and_field