Merlin Prismriver is a fictional character from the Touhou Project series. She is one of the three Prismriver sisters, a group of ghostly musicians known for their lively performances. Merlin is the middle sister and plays the trumpet, contributing bright, energetic sounds to the trio’s music. In the series, she appears as a background character and a boss in certain spin-off works, representing the playful and whimsical side of the Prismriver ensemble.