Neechan wa Chuunibyou  

My Big Sister Lives in a Fantasy World, 姉ちゃんは中二病

Sakaki Yuuichi was a high school student when he discovered that he had the ability to see people's soul powers, which were called "Lord of Soul." His sister named this power. Suddenly, suspicious individuals with labels such as "Undead," "Witch," and "Vampire" started appearing around him. Additionally, Natsuki, a serial killer, approached Yuuichi, who was confused by these events. This is the beginning of a fighting comedy story about the "strongest" brother who underwent the training of his "chuunibyou" older sister.

Neechan wa Chuunibyou was published digitally in English as My Big Sister Lives in a Fantasy World by J-Novel Club from December 3, 2016 to December 30, 2017.