This touhou project paper toy is Merlin Prismriver, one of the many characters in the Touhou Project, she is a poltergeist and one of the three Prismriver Sisters, the papercraft created by Ponta, and Graphig Template from Nasos. There are also Lunasa Prismriver and Lyrica Prismriver on the site.
Merlin wears white clothing, is a trumpeter, and is the second sister. She has blue eyes, wavy light-blue hair, and is always seen with her trumpet floating nearby. Her band uniform is pink, with blue and black trim. Her hat has a blue sun decoration at the peak. Her alternative outfit in Phantasmagoria of Flower View is same as her normal outfit, except her dress is cyan, and her trumpet is silver.
You can download this papercraft toy here: Touhou Project: Prismriver Sisters - Merlin Prismriver Graphig Template Free Paper Toy Download