Princess Rosalina from Mario Bros. series

The image features Princess Rosalina from the Mario Bros. series, a blonde-haired woman wearing a blue dress with long sleeves and an off-the-shoulder neckline. She has a silver crown on her head adorned with two jewels, one pink and one blue. The background is blurry but appears to be a room or hallway with white walls and greenery visible in the top right corner. The overall impression is that of a character from a video game or anime, possibly cosplayed by someone at an event.