Summary
Kono Naka ni Hitori, Imouto ga Iru!
Mikadono Shougo is the son of an industrial magnate named Mikadono Kumagorou, who passed away. As a final wish, Kumagorou gave Shougo a condition before Shougo can inherit the family legacy — find a female mate at school. Shougo transfers into a school to fulfill that condition. However, he learns that he has a younger sister who was separated at birth. He does not know what his long-lost sister looks like, but she happens to be one of the students at his new school.
- Chapter 6 - My Little Sister and I Are Lovers April 2, 2021
- Chapter 5 - The Hero of the Little Sister is Her Big Brother April 2, 2021
- Chapter 4 - My Classmate Became My Little Sister April 2, 2021
- Chapter 3 - Just Who is My Little Sister! April 2, 2021
- Chapter 2 - The Younger Sister and the Dance in the Moonlit Night April 2, 2021
- Chapter 1.3 - The Birthday Cake from my Younger Sister (Part 3) April 2, 2021
- Chapter 1.2 - The Birthday Cake from my Younger Sister (Part 2) April 2, 2021
- Chapter 1.1 - The Birthday Cake from my Younger Sister (Part 1) April 2, 2021
- Chapter 0.1 - Extra April 2, 2021
- Chapter 0 - Prologue April 2, 2021