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