1girl, adjusting_clothes, adjusting_swimsuit, animal_ear_fluff, animal_ears, ass, ass_focus, beach, beach_umbrella, bikini, bikini_skirt, black_bikini, black_hair, blue_archive, blue_sky, blush, breasts, cat_ears, closed_mouth, cloud, cloudy_sky, day, extra_ears, frilled_bikini, frills, from_behind, halo, long_hair, looking_at_viewer, looking_back, official_alternate_costume, outdoors, purple_eyes, ryuinu, sand, serika_(blue_archive), serika_(swimsuit)_(blue_archive), sky, small_breasts, solo, swimsuit, twintails, umbrella, underboob, very_long_hair