Upon meeting a young boy named Seita who makes a living as a pickpocket, Gintoki discovers that he is pickpocketing out of a desire to meet his long-lost mother, Hinowa, Yoshiwara's number one courtesan. Gintoki and his friends venture to Yoshiwara to fulfill Seita's wish, but standing in their way is Housen, the Night King who rules Yoshiwara.
