Nariakira's Secret Orders - S1.E18

After returning to Satsuma, Naogoro decides to marry Ochika. In Edo, the day of Atsu-hime's wedding, which was canceled after the big earthquake, is finally rescheduled. On the eve of Atsu-hime's departure to Edo castle, Nariakira confesses to Atsu-hime his true intention for arranging her marriage; if she is unable to bear an heir to the Tokunaga family, she was to persuade Iesada to make Yoshinobu, the head of the Hitotsubashi family and Nariaki's son, the next shogun.