background animation, darling in the franxx, hair, kazutaka sugiyama, hiro (darling in the franxx), 1girl, zero two (darling in the franxx), pink hair, 1boy, long hair, black hair, horns, bodysuit, pilot suit, uniform, oni horns, hairband, red bodysuit, white hairband, red horns, military uniform, military, hetero, sitting, holding hands, couple, looking at another, bangs, window