Read manga: With!!

manga
Other name: with!! ; With
Artists: Saitou Ken
Status: ongoing
Latest chapter: Vol.4 Chapter 17 : End
Updated at: Aug 25, 2019
Summary:

Masago is an average student. Everything about her is average except for her older brother, Shirou. He's the president of the student council and everyone admires him. One day, while walking home with her brother, they get into an accident and her brother dies saving her. After Shirou's funeral, Masago goes to the house of her brother's best friend, claiming to be her older brother.