akira hamaguchi, darling in the franxx, effects, liquid, 1girl, hiro (darling in the franxx), 1boy, pink hair, zero two (darling in the franxx), long hair, black hair, swimsuit, horns, topless male, cloud, sky, day, water, ponytail, one-piece swimsuit, closed eyes, oni horns, hairband, hetero, couple, partially submerged, blue sky, red horns, anime coloring, outdoors, open mouth, bikini, white hairband