I wasn't expecting a recap episode, but here we are. This episode is narrated by Kakyo, and we initially learn more about his relationship with Hokuto, Subaru's sister. This helps us understand his suffering a little better and reveals his wish. From there, Kakyo recounts to Kamui the main events of the anime that relate to him. I wouldn't say it's an episode you can skip, as in the end, Kamui finds hope to change his fate and continues wishing for a better future.