1990s_(style), 1girl, barefoot, bikini, blanket, blonde_hair, butt_crack, closed_eyes, endou_akira, hairband, kai_tomohisa, long_hair, lying, on_stomach, red_bikini, retro_artstyle, sentimental_graffiti, side-tie_bikini_bottom, smile, solo, sweat, swimsuit, untied_bikini