air_mattress arms_up asahina_yuko bikini blue_hair brown_hair casual_one-piece_swimsuit crossed_legs day dress fujisaki_shiori green_hair hair_bobbles hair_ornament hair_rings hammock hat high_ponytail highres himoo_yuina ijuuin_rei inflatable_raft innertube island kagami_mira katagiri_ayako kisaragi_mio kiyokawa_nozomi kokura_masashi koshiki_yukari logo long_hair mikihara_megumi multiple_girls nijino_saki non-web_source official_art one-piece_swimsuit open_clothes open_shirt outdoors outstretched_arms palm_tree pink_hair polka_dot_innertube print_innertube purple_hair reclining red_hair saotome_yumi short_hair shorts sign sitting sleeves_rolled_up soaking_feet splashing spread_arms standing straw_hat sundress swimsuit tatebayashi_miharu tokimeki_memorial tokimeki_memorial_1 tree updo wading