Osamake: Romcom Where The Childhood Friend Won’t Lose Vol. 1

Sueharu Maru is a 17-year-old second-year high school student who has never had a girlfriend. He lives next to his childhood friend Kuroha Shida, a cute girl with an older sister vibe. Kuroha has a thing for him and ends up confessing to him, but he rejects her. He’s hoping to win the heart of classmate Shirokusa Kachi, a beautiful girl and a successful novelist, whom he has been in love with since the winter of his first year in high school. However, he becomes dejected after confessing to her and finding out that she already has a boyfriend! But then Kuroha approaches him with an idea: to get revenge on them both!
Notice: This book is written in Japanese.