The anime includes two extra tales showcased as OVA installments. The first episode, named Episode 0, chronicles the heartbreaking split of Ritsu and Takano, who were together during their teenage years but ended things on a sour note. The audience is privy to the details of their story. In Episode 12.5, Hatori and Chiaki go on a journey to visit Chiaki's relatives, which becomes uncomfortable due to unforeseen circumstances.