A medium shot from a 3/4 view featuring a cheerful girl themed after an arapaima, captured in a dynamic, leaping pose with her body slightly tilted and one foot lifted. She has long, pastel red twintails with fluffy waves reaching her waist and large curls at the ends, paired with black-streaked bangs, aqua blue eyes with fish-scale highlights, and a beaming, innocent smile with flushed cheeks. She wears a white T-shirt with a small arapaima and watergrass print under an oversized pastel red hoodie featuring black trim, fin-like hood ornaments, scale patterns on the sleeves, and a fish-shaped zipper charm. Her attire is completed with white frilled shorts, a black ribbon belt with a fish buckle, a mini pouch, white knee-high socks with red ribbons, and thick-soled sneakers. She is adorned with fish-scale jewelry, a black choker, and a fluffy red tail with black gradients, while translucent red-black fin accessories accent her back. The scene is set in a dreamy Amazon River environment with watergrass and bubbles, illuminated by soft underwater light. The atmosphere is a blend of sweetness and coolness, utilizing a pink-lavender palette with pastel gradients and a cozy, moe anime aesthetic.