Nabari no Ou (2008)

Season 1: Episode 11

Raimei, released from the hospital, wants to retrieve the Black Gamon. She and the group encounter Gau, a member of Kairōshū. At Raimei's home, he tells her the truth about the day Raikō killed the Shimizu. Raimei returns to the site of their fight and, after seeing Raikō there, demands her sword back. During the ensuing battle, Raikō, about to finish Raimei off, accidentally slashes Gau, who jumped between them. Later, the siblings are seen in the hospital where Gau is being treated. Raikō returns White Gamon to where it belongs.