Transform the provided image into a picturesque after-rain scene. Integrate a vibrant and luminous rainbow, prominently arching across the sky. Ensure the foreground features a wet ground with numerous puddles, vividly reflecting the brilliant colors of the rainbow and the surrounding environment. Position the existing subject naturally within this new landscape, standing serenely under the luminous arch of the rainbow. The scene should convey a sense of freshness and wonder, with soft, diffused lighting characteristic of post-rain conditions. Maintain a photorealistic style and a naturalistic composition, capturing the beauty of the moment with depth and clarity.