1girl, armpits, arms_behind_head, arms_up, artist_name, bikini, black_hair, blue_bikini, blue_eyes, blue_sky, breasts, cleavage, cloud, cloudy_sky, dated, day, girls_und_panzer, halterneck, horizon, island, large_breasts, long_hair, looking_at_viewer, matsui_yasutsugu, megumi_(girls_und_panzer), navel, ocean, open_mouth, outdoors, palm_tree, side-tie_bikini_bottom, signature, sky, smile, solo, standing, string_bikini, swept_bangs, swimsuit, tree