1girl, ahoge, barefoot, blush, feet, flexible, foot_out_of_frame, grin, huge_ahoge, legs, long_hair, lying, matatabi_(2ccp), new_school_swimsuit, on_stomach, one-piece_swimsuit, onii-chan_wa_oshimai!, oyama_mahiro, school_swimsuit, smile, soles, solo, stretching, swimsuit, toes, wet, wet_clothes, wet_swimsuit, white_one-piece_swimsuit