Estina Nono is one of the main antagonists of Astebreed. She became part of Lucis, and she is also Fio's twin sister, being the older of the two. Like Fio, she goes by her nickname Esto. During the prologue sequence, she stayed on the Mobile Planet to allow Fio and her father Grato to escape. In the process, however, her mind was deeply affected, and she began her revenge against both the Fliune and the Terrans for being abandoned. Eventually, after encountering Roy and Fio, she redeems herself and joins Roy and Fio.