Sun Mingmei, along with her twin sister Sun Daiyu, is the daughter of adventurers and granddaughter of a doctor who is also a very strong Spark. She has a good chance of being a Spark herself. Mingmei was a student on board the Castle Wulfenbach, almost certainly because of the friendship between her grandfather and Baron Wulfenbach. She is a fencer, although of undetermined talent; she quickly volunteers to go help Gil and Agatha fight Slaver warrior bugs. After Agatha's escape from the Castle, she was sent home as were the other students, to reappear (probably) much later in a different context.