Bleublanc (ブルブラン, buruburan), also known as the Phantom Thief B (怪盗紳士, kaitou shinshi; 怪盗B, kaitou bii), is associated with Ouroboros as Legion No. X. Bleublanc is the only Legion agent to date that participated in both the Gospel Plan in Liberl and the Phantasmal Blaze Plan in Erebonia.