Geboku Tenjite Hana to Nasu

Shigure Rin, a high school girl who lost her family at a young age and is now completely alone. Due to certain circumstances, she was bullied at the orphanage and ostracized at school, enduring a painful daily life. Despite this, Rin lived with the hope of reuniting with her "older brother," who she had been separated from eight years ago. However, her daily life is completely transformed by her encounter with a single "demon."

Source: Comic Days, translated