A full body shot from a low-angle view featuring a modern Japanese high school girl riding atop a massive sea dragon, Lagiacrus, as they glide through a sparkling ocean. The girl, with a short black bob haircut and a bright, adventurous expression, is seated firmly on the dragon's back, gripping its scales tightly with both hands for balance. She is dressed in a classic summer school uniform, consisting of a short-sleeved white collared shirt and a pleated skirt that flutters in the wind. The colossal sea dragon has iridescent blue scales and powerful fins, surging through the deep turquoise water, creating white frothy waves and splashing droplets around them. The background is a wide expanse of a sun-drenched sea under a clear blue sky with fluffy white clouds. The lighting is bright and natural, with sunlight reflecting off the water's surface, using a vibrant color palette and a crisp, clean anime illustration style that conveys a sense of freedom and fantasy.