1girl, ahoge, animal_ears, arknights, blush, breasts, brown_eyes, brown_hair, choker, covering_mouth, grey_background, large_breasts, looking_at_viewer, lying, navel, on_back, otter_ears, otter_girl, roberta_(arknights), rryiup, shirt, short_hair, simple_background, solo, stomach, twitter_username, upper_body, white_choker, white_shirt