1girl, animal_ears, arknights, bare_shoulders, bikini, blue_sky, breasts, brown_eyes, brown_hair, cloud, cloudy_sky, cowboy_shot, from_behind, jacket, koba_(jdhikdjdkfiwufh), looking_at_viewer, looking_back, official_alternate_costume, open_clothes, open_jacket, otter_ears, otter_girl, otter_tail, outdoors, roberta_(arknights), roberta_(summer_flowers)_(arknights), short_hair, shorts, sideboob, sky, solo, swimsuit, tail, wading, water, white_bikini, white_jacket, white_shorts