Siren's Key

Ella, a flower‑shop keeper with ice powers, and her shapeshifting companion Pip fight monsters spawned by demonic energy. Police officer Nathan uncovers her secret identity. A cult tries to free the sealed Demon King. Though she holds fragments of the ancient Ice Queen’s soul, Ella has no royal memories. After harsh battles and great sacrifice, she defeats the Demon King, loses her memories, and reunites with Nathan running a small flower shop.