Episode 13 of the tv series was an unaired episode from the series. the story followed Shougo, where he was left a huge inheritance by his late grandfather. but before he was able to claim the inheritance, he had to start attending a particular school and find a girl to marry. with all the girls friendly towards him, Shougo just had to find someone that shared the same interest as his. however the twist was having his long lost sister among these girls.
this extra episode had not much difference compared to the series' 12 episodes. it was a whole independent episode by itself and could covered all the 12 episodes perfectly. mostly it was about what Shougo thought about the girls that surrounded him while giving each of these girl a characteristic that make them different from one another.
some background on the anime:
- episodes: 1
- director: Munenori Nawa (名和宗則)
- released: 2013
- language: Japanese
- genre: Comedy/Romance
- Kono Naka ni Hitori, Imouto ga Iru! (2013)
- Kono Naka ni Hitori, Imouto ga Iru!: Ani, Imouto, Koibito (2013)